Cutting mat, craft knife, Duck Tape(this is the preferred brand by our enthusiast), scissors and a straight edge if you need it.
Start by cutting ten 8 inch strips of Duct Tape. Stick two together, sticky sides facing each other, to make a double-sided 8 inch strip.
Next, cut two 3 inch sections of duct tape. Place 1/2 of one strip on one end and flip over to adhere the sticky side to the other side of the wallet. Repeat with the other 3 inch strip. You have now effectively made your bi-fold wallet.
If you want, you can add some flair to your wallet with additional coordinating colors of duct tape. Mr. Duck Tape, here, has quite a selection of wallets he's made in recent months. He has made bi-folds, tri-folds and ones with id holders. Mr. Duck Tape hopes this tutorial was informative and helpful.