Made from an old bag strap (one of those extra straps that you get when you buy travel bags - I have at least 5 of them), pieces of a leather belt and some buckles and studs. I had to hand sew the leather parts because the sewing machine needle wouldn't go through it.
The leather and studs are from an old belt that fell apart after some 10 years of wear, and the "buckles" are actually strap adjusters from some old (completely and utterly destroyed and unusable) tie-down straps I found in the garage, so I didn't spend anything :)
If you want to make this, you'll have to make sure the leather you use on the ends is strong enough to hold your guitar! It has to be really thick, like from a one-ply belt or leather shoe soles.