Inspired by a couple of TSS users over the years who do doodles inside their jackets, I had done this in the past and it most of them are perished. Here are some recent cool sketches that I did mostly on Sharpie pen (not the marker)
Took these pics before I cut off the sleeves. Turn the sleeve into patches and may be placed somewhere in the near future.
I am currently working on another one, will probably post it when it's finalized some day.