Made out of denim scraps from my mom hemming my little brother's pant cuffs. Very simple, but the difficulty depends on what material you use. It might be simpler just to use a pant leg, but we didn't have one laying around or anything.
READ ALL STEPS BEFORE EVEN BEGINNING!!!
Step 1: What you'll need
-Some sort of fabric, cloth, material, etc., including leather/suede.
-The appropriate sewing stuffs (such as needle, thread, scissors, and superglue if you're bad at tying knots)
-A water bottle (to check for size. Preferably full when testing for strength)
-A well-thought-out plan (or yours will end up BADLY!)