there are several ways - I overlap the pieces slightly then run a rotary cutter down thru the doubled portion - when I throw away the scrappy edges that have been cut away, I then have two perfectly matched cut edges, and I butt them up against each other and use the widest zig=zag to stitch them together...no double thicknesses of batting to deal with in the final product..and I don't have to tug and push the edges to match.