Yes, use the Pigma pens, then heat set the ink with a dry iron. Expanding on the clipboard idea, take a manila file folder and on the outside, cut out a square slightly smaller than the finished size of the block (for example, cut the fabric square at 5-1/2" for a 5" finished block; cut the hole in the file folder at 4-3/4" square. On the inside, trace the outside square and use double-sided tape to tape a 5-1/2" square of fine grit sandpaper over the tracing so you will know exactly where to place the fabric square. For the example below, I used a plain, brown manila folder, but they come in many colors. You could also set up a table, make several of these folders and write the instructions on the front. But it is always better to have someone sitting with them to make sure the signers are doing it right.
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