The trick to Olivia Palermo's straight hairstyle is to start with nourished strands, says Nicholas Penna Jr., owner of Salon Capri in Newton, Massachusetts. "Healthy hair is easier to manage and it reflects more light."
1. After shampooing, smooth on a deep conditioner like Kérastase Chronologiste($145; kerastase-usa.com); let it sink in for five minutes, then rinse. When you're ready to blow-dry, flip your head upside down and blast your hair with heat until nearly all of the water has evaporated. Stand up as you finish drying, using a brush to stretch out strands of your hair.