Test that your audio board is working! Plug in the battery pack and switch it on. Use an alligator clip or piece of wire to connect GND to pin 0. A sample sound should play.
Plug in the audio board over USB and load the sounds you like. Refer to the Audio FX Board guide for more info on loading sounds.
Use a needle and thread to secure the memberane switches to your jacket.
Also tack down the speakers and sound board using the provided mounting holes. Restitch any seams you cut with the seam ripper and tack down any remaining wires running through the inside of the jacket. Enjoy!