WHAT LOOKS MODERN: The best blowouts right now are about full hair that moves, with volume at the crown — not the flat, curtainlike locks of seasons past. "You want pretty, straight hair — not flatironed hair from roots to ends," says Jennifer Aniston's mane man, Chris McMillan.

HOW TO:Begin with a smoothing product like Matrix Design Pulse Thermo Glide Express Blowout Crème ($14) on wet hair, and blow-dry with a round brush. To get Naomi Watts's sleek look, iron only the last few inches of your hair after drying so you still have volume at the top. If you want Jessica Biel's movement, use a small round brush and skip the flatiron. Finish with Fekkai Advanced Brilliant Glossing Sheer Shine Mist ($23).

WHAT LOOKS MODERN: Hair that is smooth on top and textured on the bottom, for an effect that's elegant and controlled, not messy or beachy. "This wave is attractive because the hair moves and looks effortless," says hairstylist Harry Josh, who works regularly with celebrities like Jennifer Garner and Gwyneth Paltrow.

HOW TO:Got thick, unruly curls? Use a smoothing defrizzer like Paul Mitchell Super Skinny Serum ($17.99) and blow-dry with a round brush to create a polished surface. If your hair is straight and fine, boost body with a volumizing mousse — we like Pantene Pro-V Fine Hair Solutions Triple Action Volume Mousse ($3.99) before blow-drying — or try starting off with day-old hair, which can hold a wave better than squeaky-clean locks, says hairstylist Louise O'Connor, owner of the OC61 Salon & Spa in New York City.

WHAT LOOKS MODERN: A twist on the feminine '40s look, with more movement, less structure, and hair tucked behind one ear. "Old-Hollywood waves are such a great style because it looks like a lot of effort has been made, but it doesn't take a lot of effort to get," says hairstylist Mark Townsend, who coifs stars like Maggie Gyllenhaal.

HOW TO:Protect your hair from heat damage by applying John Frieda Frizz-Ease Heat Defeat Protective Styling Spray ($6.49) to dry hair, create a far side part, and set hot rollers on the top, sides, and back of your head for about 15 minutes. (For longer locks like Anne Hathaway's, use large rollers; if your hair is closer to Gyllenhaal's length, try smaller ones.)

WHAT LOOKS MODERN: Flirty '50s tails set high on the crown with lots of bounce. "Adding pouf to your pony always makes it a little bit dressier and gives it something extra," says Joseph.

WHAT LOOKS MODERN: Carey Mulligan's versatile pixie is proof that short hair doesn't lock you into just one style. The key to getting a nighttime look is lots of shine, says Mark Townsend. And with the right products, the texture goes from sculpted to modern-day shag.