Step 2: Cutting stuff! Attack that tire, baby.
if your tire is a foldable type like mine, the bead is a soft material you can cut with scissors. If it's the more common regular type of tire, the bead has metal wire in it, and you'll need to use wire cutters.
cut off the tire beads, as in the photo. cut them as close to the edge as possible, since you need all of the sidewall to make the inside of the wallet.
Inner tube card holder:
Guess what? it turns out a fat tire inner tube is just the right size to fit a credit card inside of it!! I thought this was a pretty cool discovery. If you have multiple cards stacked inside one innner tube piece, its pretty easy to slide them in and out of it, yet the fit is snug enough that they absolutely won't fall out on their own.
I like the idea of using an inner tube for the inner part of a tire wallet. It's like you just cut a hunk out of your wheel and said 'heh, dat's my wallet!'
So, also cut out about the same length of inner tube. I trimmed mine further by folding it in half and cutting a semi circle or a v shape (last pic). this allows the card to fit inside but still have an opening so you can see the cards and easily get your fingers in there to grab 'em. If you want a stealthier look, you can keep them intact so the cards hide completely inside. I like that look too. But i recommend cutting at least one end so you can push the cards out (more about this to come, with pics, in a later step)--and that end will be hidden anyway in the finished wallet if you do it the way I do.