How do I troubleshoot a faulty starter in my Audi A5?

I have noticed that my Audi A5 is having trouble starting. What steps should I take to diagnose and fix a faulty starter?

First, make sure the battery is fully charged and the connections are clean and tight. If the battery is fine, then check the starter relay and fuse. If those are intact, it is likely that the starter itself is faulty and needs to be replaced.

Another possible issue could be a faulty ignition switch. You can try using a spare key to start the car, as the contacts in the ignition switch can wear out and cause starting problems.