But there’s something to be said about using those stones at home, especially if your cracked, dry feet are screaming for a little TLC. Here’s what you need to know about pumice stones, plus a step-by-step guide to using them at home. It’s time to take soft, supple skin into your own hands (and feet). Today, you might use one to manually exfoliate dead skin and callused areas; however, you don’t want to rub the stone on the delicate skin on your face. According to board-certified dermatologist and founder of Visha Skincare, Purvisha Patel, M.D., “The uneven, sharp, abrasive nature of the stone could create microabrasions on the surface of thinner skin.” To reap the benefits of a pumice stone without scratching up your skin, it’s best to stick to thicker areas, like the soles of your feet, elbows, and knees—areas vulnerable to some roughness. If you have sensitive skin, however, you might want to stick to just the feet: “It can be abrasive on the rest of the body,” explains board-certified dermatologist and founder of MMSkincare Ellen Marmur, M.D. You may even go so far as soaking the skin, especially those rougher areas that may require a little more love. “When washing thicker-skinned areas (such as your feet), it may be better to soak in warm water for five minutes before using the stone,” Patel says. That way, the water can penetrate the skin, making dead cells easier to remove. As board-certified dermatologist Loretta Ciraldo M.D., FAAD, once told us about lukewarm baths, soaking can actually swell up the surface area of the skin, which allows for more penetration of good-for-you ingredients (applicable especially if you add soap or an oil to your water for an extra-softening boost, as Marmur suggests). After the soak, skip the towel-dry. You always want to use the pumice stone on clean, wet skin, says Patel. Be sure to stop when you’ve reached a desired smoothness (about two to three minutes does the trick, says Marmur), or when the dead skin stops clinging to the pumice stone’s pores. In terms of the actual stone’s size, they vary—the best one for you should fit comfortably in your hand, says Patel. Not too big, not too mini—the Goldilocks of pumice stones, if you will. But pumice stones aren’t for everyone; that said, check in with yourself as you exfoliate: “Stop immediately if the skin becomes tender, sore, or starts to bleed,” Patel warns. Red, inflamed skin is not a good sign, so be sure to contact your dermatologist if you think you might be experiencing an adverse reaction. Another warning worth mentioning: Never share your pumice stone with others, says Marmur. Even if you clean your stone regularly, dead skin and bacteria can still lie within the pores; you don’t want to be sharing those potentially contaminated tools, especially on areas where you create open micro-abrasions.