Forgive the photos, the brightness got messed up on upload.
Plastic card for sizing
Scissors Razor (Cutting board to go with it)
Ruler (if your picky like me)
I want to thank Dan who posted the current goto instructable on duct tape wallets, it was my first :)
Step 1: Main money pouch
Then cut 4 more pieces of equal length. Lay the first on top, sticky side to sticky side, letting half the strip go over the edge. Lay the rest down, overlapping the top piece again by about 1cm (1/4 inch). The final piece should only cover half the bottom piece. CAREFUL laying the sticky side together, as it is very hard to separate the tape if you mess up.
Fold the exposed top and bottom pieces over. Now you have your duct tape cloth! Trim both sides to around 20cm (8 inches).
Finally, fold the cloth in half. Cut two pieces of tape a little bigger then the height of the wallet. These will be inside of the pouch. Place them on the outside, half hanging over, at the halfway mark of the wallet. Fold them in, and fold up the wallet. (Power tip: if you fold the wallet up before folding in the two inner pieces, you can see if they are too far down or up.)
Fold the two pieces sticking up down along the edge and trim the ends.