From the acrylic sheet we're going to build the box.
1. Draw out the plates for the box on the acrylic sheet (photo 1). My longer plates are 15cm x 5cm. And the squares are 5cm x 5cm. Of course you can use any size for a box you want.
2. Use the jig saw to cut the plates from the acrylic sheet. Be sure to do this as perfect as you can. Because all plates need to line up nice with each other (photo 2).
If the plates don't turn out to be equal, you can sand the sides till they all fit nice.
3. Get the drilling tool and use a drill bit that is the same size as the thickness of the headphones cord (photo 3). Then drill another hole for the adapter to go though.
When you're drilling, do this very carefully! You don't want to hurry, else you might put too much pressure on it and break the plate.