I do what's called an oriental hot rocks, and I place the rocks on a towel (they're big rocks) over the persons back. I put two on each side of the spine all the way down and then one shaped like a triangle on the sacrum. I leave them there for thirty minutes and then take them off and go into a Swedish massage. When I do a hot rock massage I just massage their body with the rocks I don't leave them on. This is just my preference I know that you can leave them on if you want. Good luck!