put the two pieces of fabric together, and cut both at the same time (so you have the same number of even slits on each side.) I would just leave them one on top of the other at your table, or station, or however you're going to have your actives and PNMs set up at, and have them tie the two pieces together from their side of the blanket.
We did those a couple of years ago. They were a big hit.
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