The 9 Hottest Hair Colors for Fall 2011

KEY COLOR NOTES If it's not natural, flame red hair can look costumey against nearly any complexion. But a coppery auburn with a wash of strawberry highlights like Stone's is flattering on skintones ranging from ultra-fair to tan and tawny. (Skip the shade if you're olive or darker.) And do take a tip from the star by asking that your brows be touched-up, too. The simple tweak enhances the overall sexiness of the shade.

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KEY COLOR NOTES "This is just such a bright sexy blond," says colorist Denis De Souza, who works with celebrities like Mila Kunis, Olivia Wilde and Rachel Bilson. "To make it work for fall, just be sure to amp up your makeup a bit. That way you won't look washed out." De Souza also points out that because the tone is slightly ashy, it's best reserved for women with fair skin. "Otherwise you get too contrast-y," he adds.

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KEY COLOR NOTES What makes this blond so unique is the layers of dimensional color: A base of toffee blond is accented with ribbons of caramel and straw. We love this treatment for women who were towheads as children and are reticent to admit they're now light brunets. It also looks great on fair complected beauties with a pinkish hint in their skin; those with yellow notes can look too tone-on-tone.

KEY COLOR NOTES Ever since ombre came into fashion in the last year or so, colorists have perfected the art of the imperceptible fade. SJP's style exhibits no such precision-and that's exactly why we love it. If you're a true brunet who went blond for summer, resist the urge to re-highlight. Trust us: The results can be spectacular.

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KEY COLOR NOTES If you've got a light chestnut base like Menounos, a scattering of sunny highlights can enliven your look. Keep things sophisticated, not streaky, by making sure the highlights are ultra-fine and placed evenly throughout the entire head, even on the underside of your hair. You'll spend a long afternoon in the salon chair-and the entire season thankful you did.

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KEY COLOR NOTES "Olivia hadn't colored her hair in seven or eight years when she came to me," De Souza confesses. "I gave her a base that accented her natural medium brown with lighter honey highlights throughout. Then I lightened the tips with a shade for tones lighter than her darkest hair. It's ombre, but without being severe. And it grows out gorgeously without becoming brassy."

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KEY COLOR NOTES Usually words like streaky, chunky and patchy aren't necessarily phrases we'd like associated with our highlights. But one look at Ciara's pitch-perfect strands changed our minds for good. Thick ribbons of a coppery blond right along the part are the perfect update to a glossy espresso single-process treatment. Ask your colorist for a few hidden streaks on the underside of your hair for a playful, peek-a-boo surprise.

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KEY COLOR NOTES Does Kunis's color look too shiny and natural to be manufactured? That's exactly the idea. "Mila has dark brown hair, so I highlighted it two levels lighter than her base," says De Souza. "For anyone with olive skin and brunet hair, this technique looks amazing. It's simple and believable, but not at all boring."

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KEY COLOR NOTES Freida Pinto's hair is so unique because it's nearly a true black, without a glint of auburn or purple in the light. Of course while the best way to get this look is to be born with it, there are a few key tricks for faking it. Ask your colorist for the deepest shade of brunet, not black, which is too severe and heavy metal for the look you're after. (Think coffee grounds, not tar.) And splurge on a luxurious glossing treatment as often as you can. Dyed black hair can look rough and flat without the extra love.

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