I just did mine and I'm not very mechanical myself. The low side is the port directly in front of the drivers side of the engine compartment. It will actually have an "L" on the blue cap. The cap is easily accessible.

Once you have it located, follow the instructions on the can etc. Make sure you have the engine running and A/C on full blast. Also make sure your compressor is running (you'll see the clutch in the middle of it spinning with the belts/pulley. It's very simple! Also, DO NOT OVERCHARGE! You will most likely ruin your compressor.