Cables for NeoPixels
Use a new pair of Molex cables and cut up a set for six NeoPixels. Make the cables the following length.
Start by wiring up the molex cable plugs to the SMD pads on the back of a NeoPixel button PCB. Wire yellow to data in, black to ground and red to the voltage pad.
Double check the wires are soldered in the correct orientation with them facing inwards.
6x Wired NeoPixels
Measure and cut 6x pairs of molex cables for 6x NeoPixels. Solder the cables to the NeoPixels. Wire the socket cables to the NeoPixel's data out pads and the cable plugs to the data in pads.
First NeoPixel Wiring
The first NeoPixel in the strand will need to have one longer molex cable (plug) wired to the data in pin. The shorter molex cable (socket) is wired to the data out pin.
The last NeoPixel in the strand only needs one molex cable (plug) connected to the data in pad. Use the following length to size the cable.
The fifth NeoPixel in the strand features longer molex cables. Use the following length to measure and cut the cables.
9x Wired NeoPixels
Double check each NeoPixel is probably wired up. Line them up in order (from left to right) and reference the photo for correct placement.