The music, sound, and lights circuits follow the blueprint set out in part 2 of this series, but now we're transferring things to PermaProto boards.
You can continue to use the Metro and Music Maker MP3 shield, as seen in the circuit diagram above, or move to the smaller Feather M0 Basic Proto with MusicMaker FeatherWing. Be aware, however, that the Feather is a 3.3V board and will need a level shifter to communicate properly with the NeoPixels.
In the diagram you'll see various parts labeled "JST" -- these are connections that can be made using multiple conductor JST connectors (or other interconnects of your chosing) in order to assist with assembly. It can be tricky to insert things such as speakers, lights, and buttons for triggers while they're connected to the circuit, so these will allow you to plug them in as you go.