When it came to accessorizing her newly platinum do for Sunday’s Grammy Awards, the always-edgy Rihanna went for some depth at the root, plunging Armani — and seriously pricey digits!

Sporting Red Carpet Manicure’s “Amor 24,” a 24-karat gold polish that retails for a whopping $5,000, the performer also added tiny dollar signs to her pinky fingers.

Brand reps tell us that upon spotting the gilded lacquer, Rihanna promised to “guard it with her life.”

Additional limited edition bottles of “Amor 24″ will be auctioned off for charity, but a more affordable version, “Award Winning,” will be available this spring on RedCarpetManicure.com for $9.99.

–Justine Harman

WANT MORE? COOL WINTER NAIL TRENDS TO TRY RIGHT NOW!

Mom-to-be Kristin Cavallari is spending a few days in New York City to attend Fashion Week — and she’s taking us with her! The former reality starlet is blogging her way through the shows exclusively for PeopleStyleWatch.com, giving us inside info on her favorite fashions, the best parties and more. Here, in her first blog, she arrives in the Big Apple and gives us a preview of what’s to come:

So excited for Fashion Week! Just got to New York and I love being in the city. New York has such great energy during this time.

This year I decided to only go to three shows. In the past, I’ve done numerous shows and it gets exhausting. I’ll be seeing Rachel Roy, Betsey Johnson and Dennis Basso. I’ve gone to Betsey every time I’ve been to Fashion Week and she never disappoints. It’s by far the most fun you’ll have at a show. Rachel Roy will be a first for me and I cannot wait. I’ve been a fan of her line for a while now. Dennis Basso will also be a first and someone that is new on my radar.

Fashion Week is definitely many a girl’s dream … and what’s not to love? I’ll be playing dress-up for the next two days and wearing some amazing outfits. You can take more fashion risks in New York and especially during Fashion Week, so I can’t wait to show you some of the risks I’ll be taking that I wouldn’t normally. Tell us: What do you want to see Cavallari wearing?

CATCH UP ON ALL THE LATEST FASHION WEEK NEWS AND PHOTOS

New week, new haircuts! Demi Lovato and Miley Cyrus both changed up their hairstyles (again) last week, sharing photos of their new looks on Twitter.

Lovato — a natural brunette who was most recently a redhead — went blonde Saturday. “Thank you SO much Nine Zero One salon for my new locks,” she wrote, asking fans for feedback. They must’ve liked the look: later that day, she Tweeted, “Haha Demi Blondevato is a trending topic?!! Y’all are funny!”

Cyrus’s change was a bit more subtle: the singer, who took five inches off of her hair last month, went a bit shorter and added some face-framing layers. Her Tweet of “You likey?” was met with compliments like “fab” and “beautiful” from adoring followers.

We love both ladies’ new looks, but want to hear what you think. Tell us: Do you like Lovato and Cyrus’s new dos?

Courtesy Miley Cyrus

TRY STARS’ STUNNING HAIRSTYLES IN OUR ‘INSTANT MAKEOVER’

What Super Bowl outburst? After a particularly rough week — where she watched her husband’s Patriots lose the big game and then shared some not-so-nice words about his teammates — Gisele Bündchen got back to doing what she does best on Saturday, walking the runway for designer Alexander Wang at New York Fashion Week.

There were rumblings of her appearance before the show (as the team at Fashionista Tweeted, “Freaking GISELE backstage at alex wang”) and once she did hit the catwalk, wearing an asymmetrical military-inspired black leather coat and matching boots, she was met with cheers.

“It was special to walk in the Alexander Wang show on Saturday,” Bündchen told PEOPLE exclusively following the show. “He is an innovative designer and a sweet person. I look forward to working with him in the future.”

Bündchen wasn’t the only big name in the house, however: she was joined by Carmen Kass, Shalom Harlow and Karolina Kurkova, who all received big rounds of applause, as well.

SEE ALL THE LATEST FASHION WEEK NEWS AND PHOTOS

Chris Martin is a lucky man! The Coldplay rocker’s leading ladies — collaborator Rihanna and wife Gwyneth Paltrow — paused for a hot shot Sunday night while backstage at the Grammy Awards, showing off their slim figures and similar, slinky gowns. Rihanna worked the room in custom Giorgio Armani (she’s currently a face of the designer’s denim and underwear lines), while Paltrow wowed in a long black number with a solid gold belt.

Later in the night, Rihanna joined Martin and his bandmates for a medley of her “We Found Love” and their “Princess of China” and “Paradise.” Rocking leather shorts and a crop top — plus her new blonde do — the singer got the excitable crowd going. Meanwhile, Paltrow introduced the night’s big winner, Adele, before the beloved Brit took to the stage for a highly praised rendition of “Rolling in the Deep.”

Rihanna and Paltrow were among the night’s few style standouts; Adele and Carrie Underwood were both red carpet winners, too, though many stars failed to impress (or shock) this time around. Though Nicki Minaj’s slightly sacrilegious look drew mild criticism, no one seemed to go too crazy this year — not even Lady Gaga (and that’s saying a lot). Check out our best dressed here, then vote on the night’s biggest risk takers here. Then tell us: What did you think of the 2012 Grammys style?

CATCH UP ON ALL THE LATEST GRAMMY NEWS AND PHOTOS

They really are lucky ladies: Samantha Titus, Katrina (Tina) Arandjelovic and Kimberly Perry are the brand new faces of Madonna and Lourdes Leon‘s beauty and clothing line, Material Girl. The girls beat out thousands of wannabe catwalkers in the brand’s “Lucky Stars” model search, and were handpicked by the mother-daughter duo to front the line.

“We set out to find someone who embodied the Material Girl lifestyle: a free-spirited girl with an interest in fashion, who isn’t afraid to express herself and let her true personality shine through,” Madonna and Leon said in a statement. “It came down to three girls who we absolutely loved and felt were true Material Girls, so we decided to make all of them winners.”

The ladies’ first ads, seem here, were shot in a New York City studio (Kelly Osbourne and Leon were both on set) and will debut in magazines, online and in stores later this month. The girls — who each won $5,000 in addition to the job — range in age from 19 to 21 and came from California, Illinois in New York. One runner-up, Briana Herrera, was named special correspondent for Material Girl and will blog on behalf of the brand.

Courtesy Material Girl

Osbourne, who’s been the face of the brand for a year, won’t appear in further ads, though she hopes to stay involved with the line. “I can’t even tell you what it’s done for my confidence,” she told PEOPLE in December. “To be a face of a fashion line? I’m not even a model citizen.”

Courtesy Material Girl

The Fashion Police star helped with the initial stages of the model search, going to open calls at malls around the U.S. before online voters — and later Madonna and Leon — chose the finalists and winners. “It gave me faith in the female kind again seeing these awesome young girls on stage,” she shared.

Be sure to check out behind-the-scenes footage of the “Lucky Stars” process (featuring Madonna and Leon) at facebook.com/materialgirlcollection. And find Material Girl makeup, clothing, intimates and outerwear at Macy’s stores and macys.com.

SHOP THE CELEBRITY STYLES YOU NEED TO STEAL — NOW!

So that’s what’s happened to all our lost socks! On Friday night at New York Fashion Week, Toni Braxton helped unveil a custom dress made entirely of socks, designed by Project Runway All Stars’ Michael Costello. The gown is the centerpiece of the “SheKnows Where the Other Sock Went” campaign, an initiative from SheKnows.com to raise money for charity.

“When SheKnows called me … I was all over it,” Costello says. “I love a challenge, and I just thought it was something that could be totally cool.”

Using more than 700 single socks, Costello created a one-shoulder gown for Braxton, which she debuted at Friday night’s bash and wears in an advertising campaign, shot by noted fashion photographer Nigel Barker. The dress will go up for auction this spring, with proceeds benefiting Autism Speaks, the world’s largest autism and science advocacy organization. It’s also a cause close to Braxton’s heart: the singer’s youngest son was diagnosed in 2003 and she serves as a spokeswoman for the group. To learn more, and to see Costello in action, visit wherestheothersock.sheknows.com.

SEE ALL THE LATEST FASHION WEEK NEWS AND PHOTOS

Jennifer Lopez‘s skin sure is glowing in her new fragrance ad — we know, because we can see it all. The sexy singer and American Idol judge strikes a daring pose — in the buff — for her new fragrance (her 18th!), Glowing.

“Glowing is such a clean fragrance,” she tells WWD of the scent, a follow-up to her first fragrance, Glow. “That’s what I’ve always been about. I like soapy, clean smells. This is a very woodsy scent. So it’s not exactly what I created 10 years ago — it’s the evolution of that.”

Describing Glowing as “earthy, clean and real,” Lopez says the fragrance is “kind of New York-y, darker and sexier.” It contains notes of cypress, orange flower, cassia flower, vanilla and cashmere musk, and as a special treat, the eau de parfum bottles light up for 15 seconds when spritzed. “We’re in the history making business, baby,” Lopez says, laughing.

Jokes aside, Lopez hopes that this is another fragrance that will last. “I always feel pressure to create a great fragrance — I always want it to be so special, this one especially because of Glow. We want it to be great, and I think it is.”

Find Glowing exclusively at Kohl’s stores beginning in May for $39-$65. Tell us: Are you a fan of Jennifer Lopez fragrances?

SHOP STARS’ SIGNATURE SCENTS

Leave it to Madonna‘s daughter to try a cool new look! Lourdes Leon stepped out on her way to school in New York Thursday, sporting a funky new half-shaved do. The stylish 15-year-old — who’s had long dark hair forever — had her hair up in a bun, bringing extra attention to the edgy style.

Leon hasn’t made drastic changes to her hair before, though she’s toyed with the idea. “I want royal blue hair but not a streak, like my entire head,” the teen designer wrote on her blog in December of 2010.

But at the time, she wasn’t so sure she’d get away with the change. “I read this blog aloud to my mother,” she continued, “and she is sitting here staring at me with no expression on her face, as if she doesn’t approve of it!” Wonder if Madonna gave this cut the OK? Tell us: What do you think of Leon’s look?

SEE THE STARS’ WACKIEST WINTER HAIRSTYLES

Fergie is continuing her foray into the glamorous life with yet another fab gig: the Black Eyed Peas frontwoman is the first-ever face of Wet n Wild. The brand announced the partnership on Friday; the singer will star in a series of campaigns beginning later this year.

“I’m someone who goes from light neutrals during the day to some really dramatic looks at night for the red carpet,” Fergie tells PEOPLE. “I love that I can find all of these colors with Wet n Wild. Plus, the company and I come from the same [California] hometown!”

In addition to serving as a brand ambassador, Fergie will launch some signature Wet n Wild products, too. “I think the brand is a realistic beauty buy for every woman out there,” she explains. “It’s beauty for all. It’s on-trend, it’s affordable and it’s easily accessible.”

The star will shoot her first campaign photos in March, and will wear Wet n Wild products to Sunday night’s Grammy Awards. “[Fergie's] versatility and range is perfectly aligned with Wet n Wild,” the company’s COO, Bill George, says in a release. “She has the unique ability to go from hip, edgy and sexy to red-carpet glamorous. We couldn’t be more thrilled to work with her.” Tell us: What do you think of Fergie partnering with Wet n Wild?

SHOP OUR EDITORS’ BEAUTY PICKS

When it came to partnering with Coty to create the ultimate perfume, Roberto Cavalli was primed for the challenge.

“I was waiting a long time to have such a special fragrance,” he told PEOPLE recently. “I spent a lot of time to create something that I really like.”

Sitting low in his chair, and surrounded by lanky employees with thick Italian accents, the storied designer detailed whittling the scent down to three key ingredients. “At the beginning they gave me a lot of small bottles and I didn’t know which one to choose because one was too sweet and the other one was too …” he trailed off. Clearly, creating a fragrance is hard work.

Comprised of a trifecta of harmonious scents — orange flower, roasted Tonka bean and peppercorn for a spicy note — the eponymous scent was created as a tongue-in-cheek homage to the designer’s late mother.

“She adored perfume,” he said, his eyes glassing over with remembrance. “She used to buy the most horrible, cheap perfume. It was strong, strong perfume. I like mine because it is soft, delicate … not too much.”

So when asked which of his A-list fans would best embody his “sexy, feminine, aggressive” scent, Cavalli was quick to choose Jennifer Lopez. “It’s for a woman full of energy,” he mused. “I can see Jennifer singing and dancing with my perfume. I would love that.”

–Justine Harman

SHOP STARS’ SIGNATURE SCENTS!

Arriving at QVC’s runway show in New York Wednesday night, Camila Alves seemed to have a little extra sparkle, in the form of a stunning three-stone sparkler on her finger. The handbag designer was out for the first time since her Christmas engagement to longtime love Matthew McConaughey, and put her gorgeous engagement ring on display for all to see.

“I am really enjoying being engaged right now … no wedding plans as of yet,” she told reporters. But speaking to PEOPLE earlier in the week, she was happy to dish on her fiancé’s sense of style. “Matthew has great taste,” she said. “He always has great opinions on what works and what doesn’t.” He even gives input on Alves’s handbag line, Muxo, which she designs with her mother. “We are one big family so we share everything — including opinions on the creations for the line.”

Alves’s latest collection, which she’ll present on QVC this Saturday, was inspired by her recent travels through Texas, Arkansas, New Orleans, California and New York. “We are really having fun mixing all of the inspirations from the various landscapes that we’ve been collecting for some time now,” she shared.

Courtesy QVC

The Brazilian beauty fell in love with fashion at an early age; her mother, a designer by trade, would let her help with various projects. “It taught me so much about design,” she explained. “And after I had moved to the States I was looking for something to do with my mom to help the family in Brazil … so we created our first handbag together.”

Though the pair has their moments — “Sometimes we butt heads like any mother and daughter,” Alves admitted — they feel “blessed” to work together. “We have a great relationship, and we create in a very unique way together.”

Catch Alves on QVC Saturday, selling the latest from Muxo (including her favorite, a leather satchel with a kiss-lock front pocket, right), plus sales from GF’s Geren Lockhart, Dennis Basso, Mark Zunino and Lori Goldstein (10 p.m. EST). And tune in Friday (10 p.m. EST) for launches from Cristina Ehrlich, Isaac Mizrahi, Fern Mallis, Karen Zambos, Marc Bouwer and Cynthia Vincent.

–Kate Hogan

SHOP STAR LOOKS FOR LESS

If Minka Kelly was nervous about walking in Wednesday’s Heart Truth Red Dress Show at New York Fashion Week, she definitely wasn’t showing it. The actress hit the runway in a glimmering, custom creation by Diane von Furstenberg, and was met with cheers from the adoring crowd.

Kelly got involved with the annual show through sponsor Diet Coke, once the company asked her to be their celebrity ambassador. “Before I got involved I didn’t know that heart disease was the number-one killer of women,” she told PEOPLE exclusively (hear more in the clip above). “If I get one girl to go to the gym one day more often than she does … then I’ve done a good job.”

Joining Kelly on the catwalk were stars like Christie Brinkley (in Pamella Roland), Jenna Elfman (in Alberta Ferretti), Rebecca Romijn (in Marchesa), Rose McGowan (in Donna Karan) and Elisabeth Röhm (in Nicole Miller). “I’m excited for Chaka Khan and I’m excited for Gloria Estefan,” Kelly revealed before the show. “I’m such a huge fan of both of them, so I’m so honored to be in their company.”

The scene backstage was lots of fun: the seventh floor of New York’s Hammerstein Ballroom was transformed into a giant salon, with hair stylists from Elizabeth Arden’s Red Door Spa, makeup artists from Bobbi Brown and nail guru Deborah Lippmann running between celebrities to primp and perfect. (Check out our Pinterest page for some behind-the-scenes photos.)

The Red Dress Show — now in its 10th year — raises awareness about heart disease and the Red Dress, unveiled by the National Heart, Lung and Blood Institute in 2002 as a symbol for the cause. For more information on prevention, and the campaign, visit hearttruth.gov.

And to help in the fight, pick up a four-pack of Diane von Furstenberg’s limited edition Diet Coke bottles ($30), sold throughout the month of February; 100 percent of proceeds will benefit the Foundation for the National Institutes of Health.

–Kate Hogan

IT’S NEW YORK FASHION WEEK! GET ALL THE LATEST HERE

Wednesday marked the beginning of New York Fashion Week, but last week, one of the city’s biggest fashionistas was already out and about. Speaking to PEOPLE Thursday at Godiva’s 2012 Valentine’s Day event at the Andaz 5th Avenue in New York, Blake Lively showed off a stunning Valentino ensemble, pairing the chic getup with — you guessed it — Christian Louboutin shoes.

The Gossip Girl star is known for her love of Louboutins — the designer even helps her decide which of his shoes to wear sometimes — but her latest interaction with him really takes their relationship to a new level. “My gosh, [the spring collection] was sent to my house today, and they’re so beautiful,” she revealed. “They’re amazing. I walked around my apartment wearing them.”

Her favorites? “These cage, crystal-encrusted shoes and one with a feather detail coming off of it.”

Lively, who doesn’t have a stylist, described her style muses as “women from times past: Katharine Hepburn, Audrey Hepburn, Grace Kelly. I love the sophistication. I love every single detail.” Sounds like she’d love to live among them, too. “I would love if I could wear little cut-off gloves every day,” she mused. “That would make me so happy. I’d go to a grocery store in a beautiful hat with lace dripping over the eye.”

But her handbag would certainly be current. “I do love my Chanel bags,” she said. “They come with me everywhere. That’s the truth.”

–Catherine Kast

SHOP HOLLYWOOD’S HOTTEST SHOES — FOR UNDER $100

Best known for her spitfire sense of humor and otherworldly good looks, Olivia Wilde’s stay-gorgeous routine is surprisingly girl-next-door.

“[I wash] and moisturize my face with drugstore brands like Cetaphil and CeraVe,” she tells PEOPLE.

And when that newly lopped do becomes a hassle, the TRON star looks to easy solutions. “I’m into cool stretchy headbands,” she says. “I throw it up and try to make it look interesting and put on a headband and then it looks like it was all intentional.”

While her beauty basics are decidedly simple, Wilde’s fitness routine runs the gamut from the serious to the silly. “I need kind of Ashtanga, like good, serious yoga,” she explains. “I never feel more beautiful than after I’ve really spent some time breathing.”

But when downward dog isn’t cutting it: “Hula hooping is one of those things that everybody sort of scoffs at,” she adds semi-seriously, “but I know people who have lost serious weight hula hooping.”

To learn more about the Revlon ambassador’s basic and bodacious beauty booty (can you say wasabi eye drops?), pick up the newest issue of PEOPLE, on stands now.

–Justine Harman with reporting by Pamela Edwards-Christiani

CHECK OUT OUR MUST-HAVE BEAUTY PICKS & CELEB GET-PRETTY PRODUCTS

She’s taken two nights off from new mommyhood this week to support hubby Jay-Z, but Beyoncé needn’t look further than her fingernails to be reminded of the new girl running the world these days: daughter Blue Ivy Carter.

“You see the blue nails. You see the IV tattoo on her finger. It’s clear that she was bringing Blue along with her because she doesn’t want to be away from her for a second,” Beyoncé’s longtime manicurist, Lisa Logan, tells PEOPLE of her Monday manicure.

Logan, who painted the singer’s fingernails with Nails Inc.’s new “Baker Street” polish (the star accented the look with a two-finger ring by Bing Bang for WeSC), says the whole experience felt serendipitous. “I don’t roll with less than 200 bottles of polish on any given day,” she explains. “When I pulled all of my colors out, [Baker Street] and two other colors were sitting at the top of the pile, and [Beyoncé] said, ‘I want this!’ She didn’t even look or blink at the other colors. She was like, ‘Oh no, I want this,’” Logan recalls. “Ironically, when I came in, the first thing she asked me for was Minx. I always have Minx nails, [but] this was the one day I didn’t have them on me!”

So how is the newly manicured mom adjusting to motherhood? “Amazingly,” Logan says. “When I see her, I’m like, ‘Girl, you’re glowing.’ She’s so elated. Motherhood is written all over her face. She’s owning it and wearing it well.”

–Carlos Greer

SHOP OUR EDITORS’ BEAUTY PICKS

There’s no limit to the number of charities celebrities seem to support, but at the moment, many are taking a stand for OrphanAid Africa, a charity championed by Rachel Roy. The designer recently created a handbag — the Rachel Roy OrphanAid Ghana clutch — designed to raise awareness about the non-profit and honor the West African nation at the same time.

“Clutches are one of my favorite shapes of handbags to carry, and when I work on product to sell for charities I want to create something that is refined, effortless and beautiful to look at … like the children that inspired the effort,” she explains to PEOPLE.

The colors in the bag — which retails for $49 — are taken from the country’s flag and washed “for a softer effect,” Roy explains. “The fabric is natural and raw; love the balance of the two.”

Hilary Swank (above) and AnnaLynne McCord have both been spotted carrying the clutch in recent weeks, with many stars sure to follow suit. One hundred perfect of net profits from sales will benefit OrphanAid, which helps Ghana’s orphans through programs in care reform, education and development. Grab the bag now on rachelroy.com.

SHOP OUR EXCLUSIVE DESIGNER DEALS

“It’s so hard to find sexy intimates at an affordable price,” Sofia Vergara laments to PEOPLE. “All women should be able to get beautiful, comfortable intimates.” Thankfully, now they can: the actress is adding sexy, lacey bras and panties to her successful Sofia by Sofia Vergara line at Kmart. Problem solved!

The star’s intimates line includes three bras and three panties in a mix of red, purple, pink, black and animal print. “Honestly I love the entire collection,” she shares. “But if I had to pick a favorite … it would be the animal-print bra because I love prints, even underneath my outfits.”

Vergara thinks sexy undergarments “set the tone” for the rest of a woman’s outfit; therefore, they should always be special. “I think every woman should start by putting on a beautiful bra and panty,” she shares. “It doesn’t even have to be lingerie.”

And for those who wonder if the line is sexy enough, Vergara promises her Modern Family character, Gloria Delgado-Pritchett, would approve. “She would love these,” she says. “All the colors and cuts make all different types of bodies look great.”

The bras and panties range from $10-$15 and will hit Kmart stores and Kmart.com in late February. Perhaps Vergara will even give boyfriend Nick Loeb a sneak preview on Feb. 14, too. “I like the classic Valentine’s Day things like flowers, dinner, maybe a movie,” she reveals. “But I like to be surprised, so hopefully he’ll come up with something fun!”

–Kate Hogan

SHOP THE LINGERIE STARS LOVE

New mom. Same old irrepressible glamour.

Beyoncé gave birth to her daughter Blue Ivy only a month ago. But in her first two nights out on the town, she’s picked up right where she left off — as one of the world’s most gorgeous and stylish women.

On Monday, she turned heads at husband Jay-Z’s Carnegie Hall concert in a hip-hugging Alice by Temperley dress and a pair of Christian Louboutins. Then on Tuesday, for Jay’s encore show, she sported a sexy, skintight black sequin cocktail dress by Monique Lhuillier.

She looked ravishing in both dresses. But tell us, which was your favorite look?

–Tim Nudd

VOTE ON MORE FASHION FAVORITES IN ‘LAST NIGHT’S LOOK: HIT OR MISS?’

You’ve had him in bed — and now you can play with him in the pool. Eddie Cibrian is stripping down (again!) for Charisma, modeling the brand’s soft towels in the sexy spring 2012 ads, shot at a private residence in Los Angeles.

Though Cibrian — divorced from Real Housewives of Beverly Hills star Brandi Glanville and now married to country singer LeAnn Rimes — knows lots of ladies enjoy looking at his shirtless pictures, he seems to keep the modeling job in perspective.

“You have a lot of people on the photo shoot looking at you, going, ‘Oh that looks wonderful, that’s unbelievable … those [towels] look great,’” he told PEOPLE in September. “I realized it was all about the product, and not about me.”

Still, Cibrian — who appears in the upcoming Tyler Perry film Good Deeds – makes it hard to focus on those towels when he looks so good drying off with them!

Find Charisma exclusively at Bloomingdale’s — and keep an eye out for Cibrian’s multimedia campaign this spring. Tell us: What do you think of the actor’s latest Charisma ads?

Courtesy Charisma

–Kate Hogan

WANT MORE GOOD-LOOKING GUYS? CHECK OUT 10 HOT PHOTOS OF RYAN GOSLING