Using a knife, with the folded edge of the sheet closest to you, cut the folded sheet from the bottom, 3/16-inch (5 mm) away from the side edge but leaving up to ¼ inch (6 mm) at the top (see step 1 for reference). So, in other words, don’t cut through fully.
Make 5 total such cuts, and on the sixth cut, cut all the way through to remove the end piece (step 2).
Unfold the piece (step 3). Carefully pick up two middle strands (step 4) and tuck one end of the piece under and through the two strands (step 5), then pull the ends to straighten (step 6) and gently throw the piece onto the counter so it holds its shape. The strands should appear tangled up in the middle but in a controlled manner, almost braided.