Find an R134a charge kit. (just ask a clerk for an AC charger for your car at a wal-mart, someone will know what your talking about). A metal tube usually runs by the radiator, and the port to recharge should be covered with a plastic cap. Under the cap will look like a spout you find on a tire to fill with air. It's recommended that the charge kit has a gauge on it so you know when you're in the right pressure range. The kit itself should have some instructions for use. Hope this helps...