The most important part in making a flashlight is creating the circuit. After all without a circuit the flashlight won’t turn on. To create your switch you need three wires, a battery, a switch, and a light bulb. To create the switch you have to connect the battery, switch, and light bulb together with the wires by soldering. When soldering you have to be careful because if you accidentally put solder on the battery then the battery can burn. After you finish the circuit you have to put the switch through the hole you made on your body. The put the Cap’s on and you’re done.