It uses warm, melted paraffin as a way to apply heat. You can buy paraffin wax kits at your local drugstore or beauty supply. A heated container safely melts the wax and mineral oil to make a paraffin bath. Dip your achy body part into the bath several times to build up a warm layer. Take it out of the bath, and cover it with plastic and wrap in a towel for 10-15 minutes until the wax cools. Unwrap and peel the wax away.
To avoid irritation and pain, make sure the skin that you treat has no cuts or sores.