"Protection is very important to me — protection against the sun, sex, and, yes, hair damage. That's why I always hoard sprays I can mist on before blow-drying or styling, and the Hair Protective Fluid ($90) from skincare brand Sisley Paris is one of the best I've tried. Not only does it smell divine, it's also kept my hair frizz and breakage-free. My only suggestion is that, because the air pump shoots out the liquid at lightening speeds, it's best to spritz into your palms then use your fingers to work it into hair." — KC