Using this 2.1mm DC power jack with a rocker switch is easy. First, plug in your power supply. Make sure the voltage is up to 16 VDC and the current is 3A or less. Then, use the rocker switch to turn the power on or off whenever you need. When you're not using the device, it's a good idea to turn off the power with the switch instead of always unplugging. This can help protect the jack and the power supply. As for maintenance, keep the jack clean and dry. Avoid getting it wet or dirty, as this could affect its performance. If you notice any issues, like the switch not working properly, check the connections and make sure everything is plugged in correctly.