(InStyle.com) -- Ever wonder how actresses like Sienna Miller look stunning 24/7? Good genes, sure. But they also get a little help from their friends
Sienna Miller and favorite hairstylist Adir Abergel: "If I worried what people thought about my look, I'd get it all wrong."
Sienna Miller and hairstylist Adir Abergel
Try to talk coifs with Sienna Miller and she'll cut you off at the pass. "I don't even own a hairbrush!" she insists. "I'm really not too attached to my hair."
No kidding. She gamely lopped off about 10 inches to play Edie Sedgwick in Factory Girl. But the actress is much less keen to part with her hairstylist Adir Abergel, for whom she has been known to cook dinner at her London home.
"Adir gets me," says Miller. "He knows I never like to look too done or polished." Her biggest challenge? "I've got quite a lot of hair, but I like it flat, so Adir squashes it down for me."
To create Miller's ideal look, Abergel flatirons her roots and combats bulkiness with Frédéric Fekkai Coiff Finishing cream. "Sienna feels most like herself when her hair is soft and airy versus set and stylized," he says.
Still, it takes effort to appear this artfully undone. It may seem like she rolls out of bed looking glamorous, but Miller says it is not that easy: "I'm very much involved in how I want to look."
Eve and makeup artist JJ Jacobucci
She dyed her hair platinum as a Philadelphia teenager, rose to fame as a hip-hop biker chick, and cavorted with a tiger -- and later Gwen Stefani -- on MTV. It seems like Eve was born edgy.
But until recently the rapper-singer-actress clung religiously to her signature look of cat eyes, dewy skin and pale pink lips, aided by the habitual application of MAC Lipglass in Malibu Barbie (she's also a company spokeswoman).
It was on the L.A. set of Eve's candy-colored video for "Tambourine" (the hit single off her fall album Here I Am) that makeup artist JJ Jacobucci motivated the star to test a new image. "JJ recently said to me, 'Thank you for letting me experiment,'" says Eve, referring to a Cyndi Lauper--inspired look that involved electric-blue eye shadow. "I have definitely opened up a lot more."
Says Jacobucci: "We were so used to seeing her in nude lips, bronze skin and comfortable colors. I push Eve to get out of that box."
The star has lately sported hot-pink lips, chartreuse highlighter on her browbones, and blue mascara with newfound confidence. "At first Eve was like, 'Oh my god,'" says Jacobucci of such intense shades. "I was like, 'Listen, trust me. I'm going to make you look gorgeous.'"
Kate Bosworth and hairstylist Renato Campora
During the last three years, hairstylist Renato Campora has seen all shades of actress Kate Bosworth.
"When I met her, she had beachy [sandy] highlights," says Campora, who brightened up Bosworth's Blue Crush--era color so she looked "more movie star, like a young Marlene Dietrich."
Campora's platinum touch sent his number straight to Bosworth's speed dial. "It's a little secret," she says of his closet coloring abilities (he's known primarily as a haircutter). "I call him months in advance!"
Naturally, she also uses him as her stylist -- it was Campora who gave her the sleek bob that solidified her status as a hair icon last year. "She was the first one to have it," he says. "And then everybody did the bob. She was the inspiration."
For someone whose biggest struggle is building volume (Bosworth has "baby angel hair," says Campora) the bob was perfect; her hair looked thicker, and it practically styled itself. "I could jump out of the shower, give it a tousle and leave," says Bosworth.
Her next experiment? "I want to be a redhead -- a deep, Karen Elson redhead. Just to go there once."
Hilary Duff and makeup artist Rachel Goodwin
When Hilary Duff first settled into Rachel Goodwin's makeup chair in 2004, she felt like she had found a soul mate. "It was really instant," says Duff, who fell head over heels for the Chanel artist's ability to create high cheekbones, luxe lashes and pale lips.
But never mind the makeovers for movie premières and music videos for her latest album, Dignity; for Goodwin, the real test was meeting Duff's family. "My mom [Susan] did makeup for Neiman Marcus, so she knows what looks good and what doesn't," says Duff.
Luckily, Goodwin wowed the 'rents. "That's when I knew it was OK -- when Susan was like, 'This is good work,'" laughs Goodwin, who now pushes the boundaries with blue shadows and white eyeliner.
"I have really big eyes," says Duff, "and for the longest time I would use black eyeliner to make them look smaller. Rachel actually made them look bigger by lining them with white. I love how she makes me see myself differently."
Now when the two get together, they share more than makeup tricks. "We see each other a couple of times a week for hours," says Duff. "We talk about boys, life and work. We know each other so well. It's like a big therapy session every time."
Rachel Weisz and hairstylist Mark Townsend
She may be an Oscar winner, but Rachel Weisz has little in common with her gilded statuette.
"In real life I'm very unpolished," says the mother of 17-month-old Henry. "Dressing for the red carpet is fantasy time, but in my day-to-day life, I'm very grungy."
This low-maintenance attitude has served her hair well. "It's in great shape," says Matrix hairstylist Mark Townsend. "Rachel's hair matches her personality: It's not overdone, not super-fussed-over. And she's incredibly approachable and sweet."
Fearless too: In 2005 the British actress sheared her locks to a half inch to play a dying woman in The Fountain. While growing out her hair, she often donned extensions.
But a year later, when Townsend suggested she wear a thicket of curly, waist-length tresses to the Oscars, the eight-months-pregnant star didn't feel so brave. "Are you sure we need this much hair?" Weisz asked.
But Townsend soldiered on, confident in his vision. "I wanted fullness in the back to balance out her silhouette," he says of the baby bump/hair bump symmetry. The romantic updo proved lucky -- and prophetic. "Now I'm growing my hair out," she says. "I've come to like it really long and unruly." E-mail to a friend
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