Place the warmer in the middle of the microwave, making sure that it does not touch the sides or door of the microwave. (Some microwaves have a rotating turntable. This is fine, as long as the warmer does not touch the sides or door when rotating.) For extra large back warmers we recommend folding into thirds, as shown in the photo. We also recommend that your microwave is clean and free of grease or other food debris, so the warmer does not become soiled.  If you use your microwave regularly for cooking, or have a busy household with many microwave users, it’s bound to get dirty.  Fear not!  Simply place your warmer on a clean microwave safe dish to prevent the warmer from picking up any food or grease.