Using this Hybrid Racing fuel pressure gauge is simple. First, find a suitable location in your vehicle to install the gauge. Make sure to connect it securely using the 1/8th NPT threaded port. Once installed, start your vehicle, and the gauge will display the fuel pressure. Keep an eye on the readings to ensure your fuel system is working properly. As for maintenance, periodically check the connections to make sure they are tight and there are no leaks. Wipe the gauge with a soft, dry cloth to keep it clean. Avoid exposing the gauge to extreme temperatures or harsh chemicals. If you notice any unusual readings or problems, consult a professional mechanic.