P.S. Here are some other duct tape wallets on this site
Step 1: Materials
Step 2: Begin to make the back and the billfold piece
Step 3: Finish the back and the billfold piece
Step 4: Create the pieces for the card pockets
Finally, stick the two pieces of 4 inch by 2 inch together to make tape fabric. Then do the same with the 4 inch by 1.5 inch tape.
Step 5: Make the piece to hold a card so that it is visible when you open the wallet
Then, cut out a piece of the tape fabric that is a bit smaller than the card you want to put in it so that the card won't fall out. Make sure that the top of it is open so you can slide the card in and out easily. The finished product should look like the piece in the picture below.