Are you planning to send the quilt to a long-arm quilter to quilt? If so, you don't have to do a thing. Just send the backing to her/him folded up along with the top. If you are quilting it yourself, you might want to cut it down a little, but be sure to leave about 6" all around the edge. That cut doesn't have to be very accurate, but you need to have excess around the edges, because the quilting often eats up backing yardage. After it's quilted, then you have to find a place to square it up (unless your long-arm quilter does it for you). I'm afraid I'm still doing the crawl around on the floor thing, but since I'm 68, I suppose it won't be for too much longer.