1. The PCB
1x n-CH MOSFET for Backlight, 10x 330Ohm Resistor, 1x 10kOhm Resistor, 4x 100nF Capacitor, 4x WS2812B adressable RGB LED, In Circuit Serial Programming header, Backlight pins (+ is square), Oled header (exposes I²C Bus), Here's the Schematic
2. SMD and Standoffs
Solder in all the SMD components (Be careful they are tiny) and place in the standoffs flush to the PCB.
3. Solder them
Solder them and make sure that they are completly flat on the PCB.
4. Encoder and Switches
Click in the switches with the LED hole facing you and place the encoder.
5. Encoder Orientation
Make sure the 2 pins face the hole.
6. Pin Placement
Bend the pins like so to make PCB installing easier.
7. Insert PCB
Insert the PCB making sure not to bend any pins.
8. Solder Encoder and Switches
Solder in the encoder and switches while pressing them into the pcb to make sure they are seatet properly.
9. Place LEDs
Insert the LEDs with the longer leg (Anode) facing the square pcb pad.
10. Solder LEDs
Solder them in place making sure they are not slipping out.
Do not remove the insulation - It protects the controller and you from desoldering it :)
12. Place MCU
Insert and solder the MCU (Elite-C/ProMicro) with the flat side facing away from the PCB.
13. OLED wires
Strip the ends of the OLED wires.
14. Solder to PCB
Solder them to the PCB (GND, VCC, SCL, SDA).
15. Solder to OLED
Clip the top two corners of the OLED PCB round to make it fit nicely into the corners of the 3d print and solder the wires the OLED according to the marking on the OLED.
16. Screw in the Covers
Screw in the two covers for the OLED and the bottom piece with the 8 M2 screws. Please be careful when screwing them in and don´t tighten them too much (otherwise they will strip out).