I have made ten biscuit quilts. Top square is 1" larger than bottom muslin square. Pleats are sewn in the top square and sewn to the bottom square. Leaving one side open for stuffing, stuff with a ping pong ball size fiberfil. Too much stuffing will make it very hard to sew squares and then rows together. Put backing piping around edge, sew backing on like a pillowcase turn out sew opening shut and tie with crochet thread at intersections.
You can also eliminate the piping and put a regular backing on it, tie and put a binding onto it.
I had a book and followed the instructions. Good luck.