I'll echo what MTS has suggested ... safety pins!
Be sure to check the show rules. When I entered my quilts last year, the show instructions stated the pocket size and it said they could be permanently on the quilt of attached with safety pins.
Also, as said, be sure to follow their rules or you might as well not take it. And don't forget your fabric samples .... that was a major issue for me, as I was digging for those for my "proof" .... and with over 50 fabrics in the quilt, not an easy task!