Not knowing just what I was doing, this is also what I did yesterday. I had to add some to the backing to make it big enough for the quilt, so did a decorative touch, wanting it to be the top. I then found the center of each piece and marked it with a big safety pin. Then I sewed the sandwich together, just the top. I put down a board and pinned. I was off a little but got half of it pinned. Now, am just going to sit in front of the TV in my lounge chair and tie. Then I'll pin the last half. I worked on the blasted thing 10 hours yesterday. What a learning curve.
Rita