After some inspiration by Artificer and some of the other talented DIYers here, I started on a couple of sporrans. My intention was to do a hunting sporran, but I initially got sidetracted with a formal one. Since the basic shape was the same, I made the basic parts for both of them at the same time.

First came the pattern. After playing around with the compass, protractor, and ruler, I came up with the following.





Next came the parts. I made two fronts and two backs. Since most of the store bought sporrans are too small, I made mine with a three inch gusset of deertanned cowhide. The fronts and backs are 9 oz veg tanned leather with more of the deer tanned cowhide glued to the front.