There are different kinds of fusible. They have a paper backing that you draw the shape of your applique on. You trim a little outside the lines and iron it to the fabric. Cut on the lines and apply it where you want on the background fabric, then press. I prefer Lite Steam-a-seam 2. It has 2 pieces of paper, will temporarily adhere and is re-positionable prior to ironing. If you go to Pellon's site, I think they show and example of how each works.