Pinout of the LEDs is as follows:
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With that, the tree wiring got relatively easy by bending the LED pins in the four different directions and then connecting all 5 Volt pins with the red wire, GND with the black and chaining data in and out either by directly soldering the pins or via the yellow wire:
I've added a photo resistor and a white diode to provide some lighting of the tree front, as at night, the RGB LEDs are so light, that the tree itself can't be seen. The resistor value also serves to dim the RGB LEDs at night.
The software driving the LEDs is basically the Strandtest one that Adafruit delivers as example for their Neopixel Library. I've modified the code a bit to also show other patterns.
In the future we will add a stand for the tree that will also house the electronics and will also host some additional surprise that I will talk about in a future post :)
[ UPDATE 2016-12-11 ]
I've added a stand and the dedicated TrinketPRO: