After retooling the knife I bought, I needed a sheath for it. It came with a crappy nylon one that didn't fit correctly even before I rejiggered it, but that wasn't going to be good enough, especially not when on a quest to try new things.
I've sewn before, but really basic stuff: reattaching buttons, fixing small holes, putting a patch on a denim jacket, that thing of thing. I've never sewn anything from scratch, let alone used leather to do it. Leather is hard.
Hobby Lobby sells bags for scrap leather for $5, as well as the waxed twine you're supposed to use to sew it, and the appropriate needles. The bag I got had a nice big piece of extremely supple brown...some kind of leather. It had the texture of lambskin but was probably deer or something.
Made a template with some cardstock and used that to get the pattern on to the leather. Cut that out, and commenced sewing. Had to cheat a little, used an x-acto blade to make getting the needle through a bit easier; and did a wrap-around stitch (I'm positive that's not the right term for it) to keep the edges together.
Then dyed it black. The dye stiffened the leather quite a bit, but a few applications of leather lotion brought it back to soft (mostly). Really pleased with how this turned out, especially for a first attempt.