Step 2: Make the coil, the panels, paint them and the case
You are free to choose your own case, so you're free to make it how do you like.
You can see in the third image the color of case before painting in black.
I make the panels from keyboard's back.
The hole from the fourth images is made for the DPST switch.
Be careful when you make the coil because if you let the wire from your hand, you must start again.