I found a wonderful pattern and explanation over at Finchingefeld's Fancies
She does a wonderful job explaining the setup. Though there are some key points:
Face the cards left and start with AD up. So AB are the ones closest to the weaver.
This was a lesson in undoing wefts. I kept getting ahead of myself and switching to the new pattern too soon and forgetting what was forward and backward. I had to remind myself that the new turn pattern was when I had the shuttle on the left side of my loom.
I also had a problem that the tension of the warping caused the loom to not be long enough at the end. At some point I had to take the whole weave off the farthest upper right peg to loosen it up enough. I'm also still having some issues with the trim getting narrower as I go, but less than before. I need to figure out how to keep it the same from beginning to end. I think the shift in the pattern in the X hides more in the looser beginning than the end. I also have no idea how to end the weaves aside from cutting the warp.
I think I might make a new pouch for Pennsic with this. I rather like it!
Finished specs:
Pattern: Birka 6
Fiber: Aunt Lydia's crochet thread classic size 10 in dark royal and natural
Cards: 11
Length: 53 inches (134.6 cm)
Starting width:12 mm
Ending width: 9 mm
Start of trim left and end right.
What to try next?