Step 1: What you need
1. an ipod nano or anything else you can get to fit (ipod mini is to big) The 3rd gen ipod (short and fat) will fit in too, but you will have to change the way you cut the foam. the newest ipod may fit, but i haven't tried it.
2. A drill bit as big as the end of a pair of headphones and a drill.
3. Styrofoam(to pad the ipod nano)
4. duct tape