Look for sheets at thrift stores or new on sale for backing. You can also use a blanket, mattress cover or maybe flannel for the middle (who is going to see the middle). You can look for clothing at thrift stores or yard sales. I made a Hawaiian themed quilt from men's Hawaiian shirts, they seem to be abundant at a thrift store near me. Look for 100% cotton material, with used clothing you know how the material will wash up. Just make sure you wash anything used as soon as you get home. If you live in an area that has freecycle you can ask for scraps from other quilters. A DP9 is easy and the squares can be turned many different ways for different looks. There are lots of other ones that I'm sure others will suggest but the DP9 patch is the best one I can think of right now. Hope some of these ideas help, remember quilts were originally made from scraps out of necessity, so whatever works for you is the right way. There are no quilt police only quilt inspectors and they are easy to please.