I need to replace a small tabletop cover (with elastic around underneath) and thought that I could combine this with getting to know my new basic Brother machine (with its 80 built-in stitches) by making a crazy quilt topper. Do you just sew a bunch of oddly shaped pieces together? Or are they put on a backing with fusible interface? I think I can figure out the add-ons like laces or decorative stitches, but I don't actually know how the topper is constructed. It'll only be about 30" diameter (round), so it doesn't need to be very strong but does need to be flat-ish (for my cup of coffee, for instance).