Put a rubber band around your battery wires as shown. This will keep the wires from pulling on the delicate connections at the top of the battery. This is good practice whenever you're using one of these lipoly batteries - it will save you a lot of heartache to cultivate this habit!
Cut a long piece of conductive thread and tie it securely to capacitive touch pad 1. This is the tooth on the left as you're looking at the face of the board.
Plug your battery into the JST port on the back of the Hallowing and the servo into port D4. If you've already uploaded your code, touch the conductive thread to make the servo react.
Screw the single-sided servo horn loosely onto the top of the servo with the included screw. Thread your thin, stiff wire through the outermost hole in the servo horn and give it a twist so it stays put.
Unplug your servo for now - we'll plug it back in through the chipboard later on.
Use a couple small rubber bands to secure your battery to the back of the HalloWing. Be sure not to block the on/off switch on the back of the board or the USB port at the top. I found it worked best to secure it perpendicular to the HalloWing.