I use my 6x24 inch ruler. I fold the length of fabric around the ruler and then pull out the ruler. I store my fabric in a bookcase and lay large folded lengths (anything over 4 yards) on shelves. For shorter lengths, I fold using the ruler and then fold in half bringing the long ends together, and then stack on the shelves like books. It is amazing how much fabric can be stored in a small space and you have a nice clear view of what is on the shelves.