DIY At-Home Blowout

Once you're out of the shower, gently press chunks of hair with a cotton T-shirt; it's so soft, it won't ruffle the hair's outer layer and bring on—gasp!—fuzzies the way a rough towel can. Next, apply a squirt of shine serum from midstrand down, recommends Arsen Gurgov, a stylist at Louis Licari salon in NYC. Doing this while hair is damp helps the serum spread more evenly.

It's best to blow-dry hair someplace other than your steamy bathroom, to escape the humidity. Tip your head over, and dry roots as you run your fingers through hair, Gurgov recommends. Straighten up while hair is still a bit damp.

Apply another round of product; during hair-raising weather, it's key to keeping frizz under control. If you have straight hair that could use fullness, go for mousse. If your hair is wavy or curly, reach for a straightening balm. Starting at the back of your head, use a wide-tooth comb to separate hair into four sections—the top, the sides and the back, explains Maury Hopson, a stylist in NYC. Tuck strands you're not working on up and out of the way with big hair clips, to keep the blast of air from causing flyaways and general mayhem.

Unclip the back section of hair. With a medium round brush, lift a 2-inch piece from the roots. Keep the dryer about 1 inch above as you firmly pull the brush out. "A shiny blowout comes from tension you create with your brush as you dry," Gurgov says. Angling the dryer nozzle down toward the ends helps the cuticle lie flat—the smoother the strands, the more light they reflect.

When a piece of hair is dry, blast it with a shot of cool air to seal in sleekness. Repeat until all the hair in that section is dry. Then go through steps 3 and 4 with the left, right and top sections. When they're all dry, mist with a flexible-hold hairspray. That's all you do—so sexy!