1. Park your car in a level area and turn off the engine.
2. Open the hood of your car.
3. Locate the headlight assembly that you need to replace.
4. Disconnect the electrical connector from the back of the headlight assembly.
5. Remove the mounting screws that hold the headlight assembly in place.
6. Remove the headlight assembly from the car.
7. Install the new headlight assembly.
8. Reinstall the mounting screws.
9. Reconnect the electrical connector.
10. Close the hood of your car.
Here are some additional tips for replacing the headlights on a 2003 VW Jetta GLS:
* Make sure that you have the correct replacement headlights before you start the job.
* Be careful not to drop the headlight assembly when you are removing it or installing it.
* If you are not comfortable replacing the headlights yourself, you can have a qualified mechanic do it for you.