1. Solder the diodes D1, D2, D3, D4. Make sure the line on the diodes is aligned with the lines on the pcb.
2. Snip the excess from the diodes. Use some of the excess wire to solder through R1.
3. Solder the headers on the PROMicro slot. make sure that the black part of the header is on the side of the PCB that says RAW.
4. Solder the switches, they only go one way!
5. If you want LEDs, solder them through the switches. Remember the short leg goes in the square pad. Snip the excess
6. Solder the PROMicro. Make sure the raw pin lines up with the RAW marking. Snip the excess of the headers.
7. Screw in the spaces and the back cover.
8. Plug in the USB. Open QMK toolbox and flash using this hex. – Download
 
To customise the keymap go to config.qmk.fm and select handwired/mechboard_micropad as the keyboard.