I just use my fingers. Years ago (mid 70's) when I was a kid starting out on long and recurve bows I used a piece of leather.The newer waxes of today howeverheat up and melteasier than they used to. You can still use one, but I don't think it's necessary anymore. I have found that it dooesn't take as much heat to get the wax into the string like it used to.