I used a pattern found on Etsy, which my husband found and asked me to make for him. For the most part, the pattern is extremely well-written--lots of pictures, however I think the author became a bit tired of pattern-writing towards the end, especially when it came time for assembly. Either that or it's a common sense thing that I'm just lacking. By the time I started assembling the second slipper, I had figured most things out, but the first one was rather tedious.
As you can see in this last picture, I "embroidered" an iron cross on the side of each tank. I use quotes because I did a really messy job here. I so wanted to be done with these things and just wasn't thinking that you could easily see the messy side if someone wasn't wearing them. Oh well. Maybe in another 7 years I'll make my husband a neater pair.