I just finished 3 hexi projects, pillow cases and sheet tops. I really enjoyed doing them, did it different from years ago, and it went Way quicker.
Once I had the individual hexies stitched over the form I pressed them, took the form out and pressed again.
I just kept them stacked neatly in a little box until I was ready to grab the next hexie.
The first time I did the never ending holiday table topper I kept the forms in until I'd stitched the one above it and working with all that cardstock made the stitching a real pain because you can't manipulate the fabric like we like to do.