Put the two edges together on something flat, like the ironing board, use 2" (or so) strips of lightweight fuseable interfacing (like we used for clothing) and iron them together. Be very careful if this is a poly batting, but works great with cotton, wool, and bamboo. Once your quilt is quilted, you'll never know, and neither will anyone else. Best of all, you don't have to wrestle with this under your sewing machine!