Is it a quilt with sashing? If so stitch down the center of the quilt to divide it in half and then across the middle to divide it into quarters. If those 2 lines of stitching look decent then smooth and re-pin one of the quarters and quilt that quarter. If that is successful, smooth and re- pin the next quarter and so on. Even if you do not have sashing lines to follow you can use the water soluble thread and stitch the quilt into quarters that you can spritz and remove the soluble after you have quilted the quarters.