I have used cotton when I started and have done some flannel.
I made large blocks about 14 inches, then started meandering on the fabric. After awhile I tried making hearts, etc. I have these blocks by my sewing machine to check my tension before doing one of my quilts now. I've done 5 baby quilts with free motion, now building a quilt frame so I can go bigger.
Closeup of the last baby quilt I made
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