When you solder the capacitor on the solar charger, fold the capacitor over so it makes a more compact shape.
Solder the leads of the capacitor to the board.
Solder the JST connector to the LOAD side of the solar charger as shown. The red wire goes to LOAD and the black wire goes to GND.
Snip any excess wire on the back side of the board as well as the leads of the capacitor.
Solder the USB port onto the PowerBoost.
Prepare a slide switch by soldering on two short silicone-coated stranded wires to two adjacent pins, then apply and shrink some heat shrink tubing to protect the connections.
Insert the switch wires from the outside to the inside of the enclosure and seat the switch in its cutout, then solder the two wires to EN and GND (doesn’t matter which wire goes to which pin) on the inside of the enclosure.
Plug the JST wire from the solar charger into the PowerBoost, plug the lipoly battery into the BATT plug on the solar charger, and connect a miniB USB cable to your computer or an AC adapter to test out the circuit.
If toggling the slide switch turns the green PowerBoost LED on and off, you’re good to go!