Always have at least one question prepared in advance. This is your chance to drill down into an area of the business that might not have been covered in the interview. Alternatively, you may simply like to ask for feedback on how you have done in the interview.

A good tip is to pick up on something that has been mentioned in passing by the interviewer about the job. Ask him or her to expand on this. Not only does it make you appear interested, but it shows that you have been listening attentively to what has been said. It should leave the interviewer with a good final impression of you.