If it's a very long piece like I would use for backing then I do a loose pleat fold and run a basting stitch through the raw edges. You can also put raw edge to raw edge and do a basting stitch. I usually buy and extra 1/4 yard for shrinkage and you would have a few scraps left. Also buy the extra for mishaps. I use color catchers and white terry cloth towels to absorb bleeds. the white can always be bleached later and are great for pressing cloths.