The second file is a PDF with complete step-by-step instructions. Everything else is just the photos of each step without words. (I'm still learning how to make a proper Instructable with words and everything.)
August 19, 2012 - I fixed the instructions. The previous design had a corner sewn into it which I thought would give the bag a flat bottom. It does not. So the instructions are even simpler than before. Just sew the shirt closed along the bottom. You can even do this by hand, as long as you use a "stretchy" stitch.
A new instructable, showing how to make a flat bottom on the T-shirt bag, can be found here: