I made this wallet, following the instructions here. The biggest difference in making mine is that I inserted a sheet of aluminum foil to block RFID devices, which can steal all your identification information. RFID tags are part of credit cards, corporate IDs, passports, etc. Two substances block RFID devices – water and metal. I inserted the aluminum foil using spray adhesive so it wouldn’t rip or make crinkly noise.
Cash gets inserted behind the dark green slots.