I ordered a bag pattern to learn how to properly fix the lining to the outside bag. It was an easy to follow pattern from http://swoonpatterns.com and I now know at least one way of putting the two sides together. The only problem I had was with the zipper tabs. Maybe stupid of me, but I did not find out until I had the bag outside finished what these tabs were for: something to hold on to when opening or closing the bag! Something I never thought of when I made the Marit prototype! I had to sew these tabs onto the bag by hand, which I still have to do to the Marit prototype. Which means I picked up two new things with one pattern! This also means that I can now start on Marit's proper bag.
The bag turned out really nice.
Here are some pictures of the Betty bag. A great bag for swimming, a night out, etc. There is one outside zippered pocket and one large slip pocket inside.