October 2015: I have reworked the pattern to make it clearer and easier to follow. There are photographs of the entire process now. They are all at the end, if you don’t want to print those pages.
If you downloaded this pattern before October 2015, the new pattern is not much different. The main differences are that I decreased the length of the top fin by two stitches and I am now calling for a size 5 needle instead of the original size 7, because the size 5 makes the fabric tighter with less stuffing showing through.