I cut the items apart at the side seams and iron fusible interfacing (thin/cheapest price) on the garment front backs. If the back is needed to make it bigger do the same to those and then cut your squares from that.
Tonya

It all depends. Sometimes themes are on the back and sleeves as well. For the one I made (my first and only one).. I went on YouTube for all my info. If you need fillers you may use some of the back.Just make sure after you have cut the pieces to iron on fusible interfacing. I arranged all the pieces on a bed before sewing.