Step 2: Get the circuit boards
Here are the Gerber files. Alternatively, You can also get the Eagle Files from GitHub and make your own Gerbers (or whatever). You can send the Gerbers to a fab house like BatchPCB or www.sunstone.com. I have used both. Sunstone's prototype service costs about twice as much and you will have boards in half the time. The quality of the Sunstone boards is great. The price at Sunstone is the same for one or two boards so go ahead and get two and consider getting two sets of electronics.
The first and third photos are boards from Sunstone and the second photo is one I did at home with a toner transfer method.