This build is based on John Park's Remote Effects Trigger box. The only difference is that we'll be using a NeoTrellis inside, instead of a Trellis. This will give us the option to have multi-colored buttons that react when we press them.
Look at the breadboard diagram to see the connections that will be made. John Park's guide goes into a lot of great detail. The connections from the NeoTrellis to the Feather are SDA, SCL, GND, VIN, and INT.