My friend, style and makeup guru Scarlett De Bease, recently turned me on to her favorite weapon in the war against telltale roots in her blog. When I pressed her for details (swearing I’d keep her hair coloring a secret!) she told me she swears by ColorMark, an instant temporary hair color that totally covers gray roots until you wash it out. What’s so great about it? “It’s not a mascara or crayon,” she explains, “and doesn’t flake or rub off when you brush your hair.” It comes in 12 shades, blending perfectly with permanent hair color. She’s not alone in her praise: Colormark was winner of Allure‘s Best of Beauty — Beauty Editors’ Choice Award. A single bottle ($21.95) may sound pricey, but it lasts from two to four months, depending on the amount of gray that needs to be covered.