Chances are good that, in search of a way to untangle your MP3 player earbud cords, you got something like Spacematter's tutorial ( http://www.instructables.com/id/Earbud-cord-wrapper-in-5-minutes-or-less!/ ). While following the instructions, I noticed a flaw: the earbuds were free to unwrap the entire cord if the notches were cut even slightly incorrectly, or you used a card that isn't very flexible, or if you had an MP3 player that wasn't an IPod (incorrect cord diameter).
Step 1: Step 1: Materials for the cord wrapper (skip if you already have it!)
This is just the cord wrapper tutorial from Spacematters, rehashed.
-Altoids tin or equivalent.
-The earbuds you want to store
-A paper clip
-Scissors to cut the credit card
-Tape and/or super glue
-(optional) Hole punch