An engineer (and even Adafruit) would recommend that you use a logic level converter so that the Pi outputs a 5v and not 3v control signal. They would also recommend using a separate 5v DC power supply. This means adding a breadboard and lots of extra wiring.
I checked with the folks at Pimoroni about how their UnicornHAT works and it turns out that as long as the current draw is safely below 1A things will probably be OK. I connected my Multimeter in series and measured 0.85A at 100% brightness. Pimoroni’s Jon said this means things will probably be OK with my 60 LED NeoPixel strip.
Plug the DIN pin from the NeoPixel or strip into Pin 18 and then connect 5v to 5v on the Pi and GND to GND on the Pi.
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