If I'm understanding right -
When you sandwiched it, sewed around the edges and turned it right side out - it was okay.
Now I get lost
Was it when you stitched around the EDGES in the ditch that you ended up with a POOF?
Or was it after you Stitch in the Ditch over the entire quilt?

Either way, IF it were ME - I'd take a seam ripper and unsew while watch tv tonight.

THEN Press it a little - make sure it's smooth, remove all stray threads and Pin Pin Pin
Straight pins long the sides and closing pins hand space apart IN the quilt.
Check to make sure there's no puckers
Don't remove pins until you've sewn everything or if the pins are in your way.

I pillowcase all of my charity quilts. The trick is to pin corners, first smooth between corners and pin midway on each side. Then, while SID in each quadrant keep smoothing as you go. Then, I do a 1.4" seam all the way around, works best with a walking foot but with out make sure it is smooth between pins and feed in and out, front & back with your hands. I never have a problem. On yours, you may be able to unseam a small way 6-10 inches and ease the fabric as you go and restitch.

I was going to try and rip some out and see if I can smooth and fix....but will see......what I did was sid around the inside design of the quilt....I did 6 inch blocks....4 across and 7 down....so I stitched in the ditch around the perimeter of that section.....

Mary

That is the reason I don't like this method.

I would like to know what it means to pillowcase a quilt? As you can see I'm new to quilting or I would know I'm sure.

To pillowcase a quilt that means to put right sides of the top and backing together with the batting in between then sew around all the edges leaving a opening for turning right side out. Then quilt.

When I did that, had to rip all the SID out---once was enough!

Oh- I actually made some little quilts that way for the hospital in San Antonio for their preemies. It does actually work for very small quilts---20X20. Thanks for the info--just hadn't it heard it called pillowcase quilting.

The two pieces of fabric are placed right sides together and the batting is on the bottom or top (one article said to have the batting on the bottom so it doesn't catch in the presser foot)

Other names: birthing, inside-out, quick-turn

I've wondered how to deal with the layer of batting outside the seam line.

Do you trim it close to the seam line or leave it? If it's left, I think it would be bulky after the quilt is turned right side out.

If it was me, rather than rip out the quilting, I think I'd take my rotary cutter to the end that was poofy and open up the seam at that end. Then cut the front to fit the back. Or was there more than just one side that was poofy? If so, I'd do whatever sides were poofy. Then I'd finish quilting and put a binding around the whole quilt.