Use your old wallet as a template and traced around the thumb slider with a pen on the Tyvek. These two sleeves will be the outer card holders. Once you outline the thumb slider, cut the hole out with a razor blade. Make sure to put an old or unused card in the sleeve so the blade doesn't cut both sides. Additionally, you should cut a quarter inch slice off the top of the sleeve (third picture) to shorten the outer sleeves relative to the rest of the wallet.