Pet snakes shed their skin through a process called ecdysis, which is also known as molting. Snakes shed their skin as they grow, with younger snakes shedding more frequently than older ones. They start the shedding process by developing a new layer of skin underneath the old one. Then, they rub against rough surfaces to help loosen the old skin, eventually slithering out of it completely. This shedding process allows snakes to remove old, worn-out skin and replace it with a fresh, new layer.