But that doesn't mean the cleansing step isn't important. While many prefer cleansing oils, Rouleau does warn that when used incorrectly they can actually block the absorption of the rest of your products. "What happens is that even if you use a washcloth, there's still a coating left on the skin," she says. "That coating prevents your next product from really going into your skin." That's why she prefers gel, lotion, or low-foam cleansers.