This should take you a few seconds. You need one Altoids lid, two rubber bands, and a paperclip. If you really want to trick out your new wallet, use thin hair elastics instead.
Step 2: Straighten the paper clip
Make the paper clip as straight as you can with a pair of pliers.
Step 3: Put small hooks in the end of the paper clip
Use your handy pliers to put small hooks in the ends of the paper clip. Make sure the hooks are in line with each other.
Step 4: Perform the next paper clip bend
Put two more bends in the paper clip. Each of these new segments should be about 3/4 of an inch long.
Step 5: Keep bending that paper clip
Refer to the image and put two 3/16" bends in the paper clip.
Step 6: Just a couple more bends...
Grip the paper clip as shown and bend it back around the pliers.
Step 7: Last bend of the paper clip
Put a little hook at the end of the paper clip as shown and you are done with that. The first one I attempted didn't turn out so well, but the second was great. Hey, it's only a paper clip. Don't give up.
Step 8: Install your paper clip on the Altoids lid
If you bent the clip correctly, it should fit nicely into the hinge slots on the side of the Altoids lid.
Step 9: Combine the two rubber bands
Loop the two rubber bands together so there is a single knot in it. You could skip this step entirely if you use a longer rubber band, but having the little knot to grip when opening and closing the wallet is nice.
Step 10: Install the rubber bands on the wallet
Put each end of the rubber band under the hook of the paper clip inside the lid where clip holds on. You may have to loosen or pinch the clip down to accomplish this, but when you are done, the rubber bands should be held in place firmly by the paper clip.
Step 11: Load your new wallet
An Altoids lid happens to hold standard credit cards and identification perfectly. Load it up with your cards and stretch the rubber bands over.