Solder a 3-wire cable to pins 34, 38, and 40 of your “Pico” board.
The other end of this cable has a plug, which fits to the NeoPixel matrix.

Detailed view of “Pico-W” boards with NeoPixel cables.

| What | Price |
|---|---|
| Pico board | 5-10 € |
| USB cable | 5 € |
| 16x16 NeoPixel matrix | 25-30 € |
| 3 pin Data cable | included with matrix |
| Sub total | approx. 40 € |
| IKEA frame | 10 € |
| acrylic diffusor | 10 € |
| Grand total | < 60€ |