You don’t need an expensive skincare product to treat rough patches on your knees, elbows, and heels. A sea salt scrub made at home will work just as well. “Sea salt is a good exfoliator because it has thicker grains that do a good job of clearing away dry skin,” Dr. Mariwalla says. Just mix one cup of sea salt with 1/2 cup of a light massage oil. “Use a bowl to make sure the mixture stays moist, like wet sand, and not runny,” Dr. Mariwalla says. It’s best to keep this scrub away from your more sensitive areas like your face and the back of your arms, though. It can be harsh on skin that doesn’t require as much exfoliation.