Sexy hair traditionally means lots of volume, big waves, and a flirty side part. But this Spring, there's a new cool-girl alternative: a tough middle part with easy, loose waves. The combo looks naturally seductive — and not just because beauties like Doutzen Kroes (above), Brooklyn Decker, and DJ Harley Viera-Newton have been wearing the style. The look has an unpretentious, uncalculated feel that makes it so appealing. (It's also more grown-up than last season's omnipresent beachy waves.)
To re-create them: Start by combing a volumizer, such as Shu Uemura Art of Hair Fiber Lift Protective Volumizer, through damp hair. (Just because you're not going for full-on glam volume doesn't mean your hair should be totally flat). Define a center part, and then tousle your hair as you blow-dry, aiming the nozzle downward to prevent frizz. Now it's time to add in the waves: Wrap small sections of hair around a large-barrel curling iron, beginning just above the ends and working up to the chin. Finally, run your fingers through the waves to break them up. If they still look a little too defined, you can take a paddle brush to them. Just go over each section once, and then break them up with your fingers again when you're done. Voilà!