@quiltnnan
Try holding your foundation up to a light and placing your fabric on the back to cover your space plus a generous seam allowance. Cut larger than you think you need when you first start...until you get the hang of it. Sew, make sure it covers the space and trim to 1/4" seam allowance or less. Trust me...a little extra fabric until you get the hang of it is worth it to minimize the frog stitching. Once you get going with this technique, scraps will work just fine for these small blocks.
