Refreshing or switching up your gray hair doesn't have to require a trip to the salon. All you need is one of the best color-depositing shampoos for gray hair, which come in two forms: Purple-hued toning shampoos that work to banish brassy undertones — ideal for people looking to maintain a cool, icy shade of silver or white — or shampoos that deposit actual, vivid colors (pink, blue, purple, et cetera), for anyone who wants to experiment with a totally new look.
But before you get to shopping, a few notes. First, if you're going the toning shampoo route, keep in mind that you won't need to use it every time you wash your hair. About once a week (or as needed) should be enough to maintain your cool-toned shade of gray. And think of your toning shampoo like a conditioner: The longer you leave it on, the more effective it will be (but don't leave it on too long, or it could inadvertently turn your hair violet). About three to five minutes should do the trick.
Also, since color-depositing shampoos can stain shower curtains, light-colored towels, and even bathroom walls, be extra mindful when you're using them (if your shampoo gets on your shower tiles or walls, just give it an immediate rinse).