After I quilt and attach binding to the front of the quilt, I trim off my excess batting and backing. This usually leaves a 4-inch column of "waste" that I hate to waste. Any large piece of backing fabric will be folded and returned to my stash, but some of the smaller sections get trimmed and made into practice quilting squares. I thought I'd show this process to you in case you want to do the same.
First, trim your excess off:
Next, clean off any stray threads and straighten your column. Fold over sections about 6" long. Note: this will produce double batting. In my case, I've been experimenting with double batting quilts. If you'd rather practice with single batting, trim out the batting so that your squares only have one layer of batting in them.
Zip your rotary cutter across, fold another section, and repeat. This doesn't have to be precise at all! Just let 'er rip!
Repeat until the column is cut up into sections. You probably don't want to do this with ALL sides of your quilt trimmings. I usually just use one side and stash the rest of my trimmings (or throw away if they're tiny).
Take your stack of folded pieces to your machine and chain stitch them across the open ends. We're not going to stitch down the sides, just the ends. This is a quickie thing. No worries about accurate seam allowances or anything.
For those of you unfamiliar with "chain stitching", it means sewing one section after another without stopping, cutting thread, restarting, etc. Here is a easy way to see what I'm talking about:
Voila! You now have a nice little stack of practice squares for quilting. Whenever I start quilting a project, I always start on a practice square to test my tension, get used to free-motion movement again, and remind my machine what it's supposed to be doing :-)
Once you have a healthy stack of practice quilting squares, you can venture into some quilting experiments. For inspiration, check out Leah Day's Free Motion Quilting project at http://www.daystyledesigns.com/. She has hundreds of quilting patterns and video demos of how she tries new things.