First thing we'll do is connect the slide switch to the Adafruit Feather. We'll need to connect two wires to the switch. These wires will connect to the enable and ground pins on the Adafruit Feather.
I started by removing one of the three electrodes from the slide switch, either the far left or right, but not the middle. Then, cut the remaining two electrodes in half.
Secure the slide switch to a pair of helping third hands. Tin the two shortened electrodes by applying a small amount of solder to each. Tinning the electrodes will make it much easier to attach wires to them.
Now we can measure two pieces of wire, each 5cm in length, and cut them down to size. These will need to be soldered to the two electrodes on the switch. Use wire strippers to remove a bit of insulation from the tips of each wire. Secure the two wires to third helping hands. Tin the exposed tips of the wires by adding a small amount of solder to them.
Now we can attach the wires to the electrodes on the slide switch. Secure the switch on to helping third hands. Using the tip of the soldering iron, heat up the electrodes on the switch and slowly bring a wire close to the electrode. Once solder attaches, retract the tip of the soldering iron and let solder solidify for 2-3 seconds. Repeat process for the second wire.
Connect Switch to Feather
Secure the Adafruit Feather to Panavise. Tin the ground and enable pins with a small amount of solder. Then, using the tip of the soldering iron, heat up the pin and slowly insert one of the wires from the switch. Repeat process for enable and ground pins.