I zigzag the pieces together with no overlap. That means cutting the edges to make them straight, if necessary. I used to hand sew pieces that had been overlapped and then cut in a gentle curve, but that was time consuming. Next I tried the tape and didn't like having to press the whole length of batting. I was afraid that machine sewing the batting would show up in the finished quilt, but it doesn't. Now that I've tried that method I won't ever go back. That said, I've been using fairly dense battings, like Warm and Natural or Soft and Bright. I don't know that I would use that method on a really fluffy batt, would have to try it to see how it handles with a zigzag.