The physical assembly of this project is pretty close to that of my electronic dice. Some of the assembly tips there might also help here.
Components (mostly from aliexpress):
- 1 × ATtiny1614 microcontroller
- 2mm PMMA optic fiber
- 1 × 10uf 0805 capacitor
- 3 × 10K 0805 resistor
- 3 × yellow 0805 LED
- 1 × coin cell battery holder
- 3 × smd switch
- 1 × smd switch
- 1 × smd slide switch