“Mask, mask, mask,” Rubenstein says. “Make sure you have at least one mask in your regular rotation. I would replace my conditioner with a mask every other shampoo if my hair had really suffered a lot of summer damage.” 

She recommends this one from Monat, which is “great for rehabilitating thrashed summer hair. It strengthens and repairs damaged hair noticeably in one treatment. After-shower care is just as important as in-shower care for damaged hair. To follow the mask, MONAT Damage Repair Bond-Fortifying Hair Leave-In Crème ($42) is incredible for damaged hair.” She recommends applying it to clean, damp hair and styling it or letting it air dry. “It protects, strengthens, nourishes, and hydrates—not to mention makes hair more manageable and smells like a dream.”