How do you replace the rear turn signal bulb in an Audi TT?

To replace the rear turn signal bulb in an Audi TT, first, open the trunk and locate the access panel on the side of the rear light assembly. Remove the panel by unscrewing or unclipping it, depending on the model. Once exposed, twist the bulb socket counterclockwise to remove it, then pull out the old bulb and replace it with a new one. Finally, reinsert the socket, secure the access panel, and test the turn signal to ensure it works.