Step 1: What You Need
1. An Arduino (I used the Arduino Uno R3)
2. An old IPod case
That's all you need at first :)
Step 2: Finding the Spot to Cut (USB-Port)
P.S. At first you need to cut out the USB-Port because it sticks out further off the board.
Step 3: Cut It!
If you're as unpaitent as I am, you can use a multitool, or dremel, what you want to call it.
When you're done with cutting or drilling through the plastic you have to make enough room so the Arduino can fit in.
P.S. I'm not that talented in fine works, my drilling looks like I searched the Area for a little Atom of Silicon or Gold, but I hope you know what I intended to do ^^
Step 4: The Same Thing With the 9V Input
Step 5: Finish It (at First...)
Thanks for reading until now! Have fun doing this by your own :)