Hardware:

After the board is populated all that is needed is to solder the display. I usually test the board and display before soldering since it is difficult to remove the display. If you hold the display at an angle, once the firmware is loaded, you can see if it works.

Firmware:

This design is based on the Arduino Leonardo and therefore uses the same bootloader. Using an AVR Programmer the bootloader can be flashed by the Arduino IDE.

Once the bootloader is loaded the demo sketch can be downloaded from the Github link and flashed the same way you would any Arduino.