Eugenia Kim, Hat Designer
Hometown: New York City (Average winter temp: 28°F)
A slouchy beret keeps your head warm without flattening your hair. Get one in lightweight wool and buy a size up. Even a quarter-inch extra around the band will help preserve your style.
Alterna Bamboo Smooth Anti-Frizz Conditioner ($20; Sephora.com)
René Furterer Karité Intense Nourishing Mask ($46; Beauty.com)
John Frieda Frizz-Ease Thermal Protection Formula ($10; drugstores)