Whilst you need to know about the job you are enrolling into, you also need to ask a few questions yourself at the interview. Towards the end of the interview you will be asked if there are any questions that you would like to ask yourself, and at this point, you need to tell the interviewer that you have at least two questions. Ask these two questions and ensure that you ask good questions, and you can be sure that the interviewer will take an interest in you.
Be sure to dress well, too. Dressing well provides a fantastic first impression. The first impression can mean a lot to an employer. So remember, speak politely and appear prompt. You need to have a good CV with you, too, to ensure that you can back up all of your claims.
If you're looking for any specific information on this kind of career or interview, then search the Internet for other things that people might have said. The Internet and forums can give you a good insight into the kind of things you need to say to be able to get a good chance at obtaining the role, and providing a great impression during your interview.