A lap quilt is any pattern or whole panel quilt that is about 48 x 54" . Any size within 6 " of this is fine. It is long enough to cover the lap and legs, and wide enough to tuck in on each side when someone is sitting in a chair. You can go wild or just tie 2 pieces of fabric together. Even get a panel of fleece which doesn't need to be hemmed, just cut out.