When I make potholders I use warm & natural cotton batting along with batting made for potholders and such(can't think of the name right off). It has a silver coating on one side. The silver coating should face the wrong side of the top cotton fabric. I use 100% cotton thread. The thermo batting can be purchased at Wal-Mart or JoAnns. For the best deal use the 40% coupon at JoAnns or watch for when they go on sale for 50% off.