Sew and flip can be done by machine or hand. The second method I call mosaic. I feel this gives a more old-fashioned and intriguing look to your quilt. Begin by placing a scrap on the muslin, face up. Cut a second fabric with a curved or shaped edge.
Finger press the shaped edge of the second piece and baste in place.
Continue covering the muslin in this manner. You will most likely end up using both methods in your block. As you work on your block, trim seam allowances and any excess fabrics away. Trim away any fabric that hangs over the edge of your muslin. If you are working with velvets, or very slippery fabrics, baste across the patches themselves with big stitches, as though you were preparing a quilt to be quilted.