I chose Simplicity 9958, which was already in my stash. In fact, it was one of the two patterns I had used to make the original tote bag. The only real changes I needed to make to the pattern were to line the bag and add inner pockets. I used a double strand of white thread for all topstitching that would be visible on the outside (I had tried topstitching thread, but for some reason, my machine was most unhappy with it.)
The lining fabric was interfaced with Pellon's ShapeFlex, as recommended by a JAF employee. The interfacing is a bit pricey for me ($5/yd), but I have to say that it worked really well - gave it stability and strength, but it still drapes nicely. I added two inner pockets. This larger one has boxed lower corners to give it more width than a patch pocket, and I added elastic to the top. It is self lined for strength and better appearance.
I also added a zippered pocket for a cell phone or small wallet. When I made my Amy Butler Swing Bag a few years ago for use at a conference, I added zippered pockets for cell phone and wallet, and I really liked it. Made it much easier to find a ringing phone. I also added a D-ring below the pocket for attaching a key leash, to make finding one's keys quick and easy.
As an extra bonus, I made a matching key leash from a Craft Stylish tutorial and a small tissue cover from a Quilting Board tutorial. Both were quick and easy, and I think they just add a little something to the bag.
I like the key leash and may make myself one soon - that would be handy if I could figure out where to attach it in my backpack. And I think the tissue cover will be a great addition to teacher gifts this Christmas! Cute and practical, and very very quick!
Despite how many times/ways I screwed up this bag, I still really liked the finished product. I cut a second one out when I cut the first, so after some "forgetting the pain" time, I'll be making it again at least once. After that, well, we'll see....