First you should gather your supplies.
You need:
8 meter 24 gauge magnetic wire
Pape cup
2 alligator plugs
Auxiliary cord
Donut magnets
Scissors/wire cutters
Tape
Sandpaper
C/D battery

Step 1: Start Model

First, wind up coil with sandpaper.
Second, wrap wire around the battery and leave about 4 inches at the end.
Third, take wire off from the battery and tape it to the bottom of the paper cup.

Step 2: Start Plugs

First, put the alligator plug at both ends of the wire.
Second, strip the auxiliary cord.
Third, plug the alligator plug at both ends of the auxiliary wire.

Step 3: Final

Now, get your magnets.
Plug in your auxiliary cord to your device.
Put the cup to your ear.
Move the magnet around the bottom of the paper cup until you hear music.