A few things that I have found that really help avoid puckering during the quilting stage are:
- iron the quilt top and backing well, and get the wrinkles out of the batting before spray baste, then take the time to really smooth out all 3 layers with your hands (gently)
- start quilting in the center of the quilt, working your way towards the outside
- check the back of the quilt frequently to make sure all 3 layers are smooth

Pin basting is drudge work for me. I use Elmer's school glue. That quilt top and backing aren't moving a smidgen. No puckers, wrinkles, or pleats.

I agree with his. Also I does no gum up the needle. There is no odor involved m

You mean regular white Elmer's glue? Doesn't that gum up your machine? And do you wait for it to dry completely?

What's happening is that the top layer is stretching as you sew. It doesn't become apparent until you have to cross another line of quilting; that's when the excess fabric that has accumulated in front of the presser foot turns into a tuck. Spray basting and glue basting help prevent this because, unlike pins, these provide the layers with continuous adhesion. Pins, in contrast, are connecting the three layers only at the pinned locations.

One thing that helps a lot to prevent these tucks is starch. Since your quilt is already basted, what I would recommend is laying it out on a large flat sheet and adding layers of spray starch. You can use a fan to speed drying between layers. Starch both the backing and the top. Starch stabilizes the fabric so it is much less inclined to stretch as you sew.

Next time you may want to spray starch the top before layering. It's also a good idea to heavily starch the backing before layering. I starch yardage with a 1:1 solution of Sta-Flo liquid laundry starch and water, "painting" this on with a large wall painting brush. I leave it for a few minutes to allow the fibers to absorb as much starch as they can, then toss in the dryer and iron with steam. This provides a much heavier stabilization than spray starch can offer. However, layers of spray starch can help a *lot* in a situation like this, where the quilt is already sandwiched.

Agree with Woody, but if you don't want glue try pulling a little taut as you pin and remember if fist distance apart. I use more pins than my friend as I have small hands while hers are enormous.

that was my first thought too... and I usually start quilting from the center of my project, working my way to the outsides as QuiltingVagabond suggested.

I keep my hands spread around the quilting area and apply fairly constant tension while quilting. I rarely have puckers.

It seems that the problem could be that the quilt sandwich is not properly done. The backing needs to be taught, but not stretched, the batting smoothed out well. When I use batting that is natural fiber (not polyester) I press it so that it is smooth. Then, the top needs to be smoothed carefully. I like to use Elmer's school glue for making my sandwich. I work in sections on a 3 X 8 foot table. I use clips on the edges of the table to hold it snugly. If you have to use your hands to push away potential puckers you are pushing that fabric somewhere else that is unnatural and probably want to form another pucker. Also, others have also suggested things to check on your machine to be sure it is set up correctly. I also sew around the parameter of the quilt 1/8 inch from the squared up edge before beginning the quilting process. This adds a measure of stability and disappears into the binding seam at the end. Hopefully, there are some helpful hints here.

. No
. No
. If I'm in a hurry I press it dry.

Search the board for glue basting with Elmer's.