Here's what I recently did.
Using a table approx. 4' x 5-6' I laid out the batting and clipped it down to the table with big black "bulldog" clips (from office supply store).
Using spray basting I sprayed across the width of the batting approx a 12 wide area.
I folded up the backing like the picture below, and with one person (my mom!) on one side and me on the other, we carefully placed the backing on top of the sprayed batting, just covering the sticky area and leaving the rest of the backing folded.
We smoothed that section and made sure all edges were adhered.
We sprayed another 12" section across the batting, laid the next fold of the backing on the sprayed section, smoothed it down well, spray the next section of batting, lay on the backing, smoothed it down, etc., etc.
When the batting and backing were fused together, I turned the whole unit over and folded the quilt top in the same manner.
Clamped the unit to the table.
Sprayed the batting in a 12" wide section as before, laid the top on it, smoothed it down well, and continued as before, fold by fold.
I have moved this quilt around, on and off the sewing table, under the machine needle and out again, folded it up to set the laptop on the table, unfolded it and began quilting again, and NOT A PROBLEM yet.
At all.
No puckering.
No shifting of fabric from edge to edge or side to side.
No failure of the fuse.
I am delighted with my first basting spray use in 15 years.
It's supposed to wash out when I finish the binding, let's all believe for that!
Jan in VA