Test to see if all of your buttons fit into the printed panels. If the holes are too tight to fit in your buttons, you can use an x-acto knife to trim off some of the edges. Fit all of your buttons into the desired spots and securely lock them in. Most arcade buttons either snap on or screw in.
Check out the Bluefruit user manual to get familiar with powering and prototyping on a bread board. Reference the Bluefruit EZ-Key pairing guide to get your module paired with your computer. It's pretty straight forward and pairs like any other bluetooth device.
You can solder wires to Vin and Ground to test pairing (those wires will later connect to the Flora or battery pack!) Don't solder headers in - they're hard to remove and will make later steps difficult. For testing, use a spare piece of wire to connect one of the button inputs (#0 thru #11) to ground in order to verify you get keystrokes appearing.
Check out the uber guide to NeoPixels to get inspired to customize these awesome LEDs. To get audio feedback on the NeoPixels, we can load up the Amp Tie Code on to the FLORA.
Stick to alligator clips for now, to make circuit wiring & testing easy