This may seem like a daunting challenge, yet you should have plenty of experience of seeing people who did well or poorly when you are a student/postdoc. Participate in those events, watch the candidates closely in their seminars and meeting with students/postdocs. What can you learn?
Surprising fact: Based on my 20+ years of experience, in almost every round of faculty recruitment, ~1 out of the ~4-6 candidates (who all look excellent on paper) would mess up
Once you make it to this step, they want you to be successful. Prove them right!
People are looking for someone who is good professionally (research, teaching, etc) and likely will be a good colleague for the next few decades.
Be yourself, but also think about what kind of colleagues you would like to have, and behave (project the image) accordingly
Introverts often suffer some disadvantages. Being shy around strangers is normal, but overly so may be viewed as cold/uninterested/immature
Show them that you are ready to take the job. If you are not sure, then why should they hire you?
Interview goes both ways. Would them want to offer you a job? Would you want to accept the offer?