Hot Stuff: 12 Beauty Breakthroughs for Summer

Hair-Color Helper

Water (from a shower or swim) swells the hair shaft and breaks up dye molecules. Wash with Nexxus Dualiste Color Protection + Intense Hydration shampoo ($11.99, drugstores). It deposits a water-repelling layer onto the cuticle that stays put after you rinse, keeping your hue true.