Setting up a tattoo gun is a relatively simple process. First, you will need to assemble the gun. This includes attaching the needle, tube, and tip. Once the gun is assembled, you will need to plug it into a power source and turn it on. Next, you will need to adjust the voltage and needle depth to the desired setting. Finally, you will need to fill the ink cup, attach it to the gun, and test it on a piece of scrap paper to ensure it is working properly. Following these steps should allow you to successfully set up a tattoo gun.