Using this Subaru OEM gasket and seal kit is straightforward. First, gather all the necessary tools for your engine overhaul. When removing the old gaskets and seals from your Subaru WRX's FA20 engine, be careful not to damage any engine components. Once removed, clean the surfaces where the new gaskets will be installed to ensure a proper seal. Then, carefully place each gasket and seal from the kit in its correct position according to your engine's layout. Remember, the actual gaskets in the kit might look different from the generic image. As for maintenance, after installation, keep an eye on your engine for any signs of leaks. If you notice any issues, it's best to have a certified Subaru dealership check it out. Also, always follow Subaru's recommended service intervals for your vehicle. And don't forget, for the warranty to be valid, the parts must be installed by a certified Subaru dealership and the part's VIN must match your car's VIN.