I pin mine no less than hand-width apart. I also take a lot of effort to tape the backing down very taut and smooth out the other layers so I can keep puckering to a minimum. Are you planning to SID? If so, you can roll the quilt in half and work at one half at a time. Don't let it pull off the table or the stitches will be wonky. Don't forget to take breaks and just have fun with it. Rome wasn't built in a day.....