The interviewers have a scorecard to rank you! Your challenge is to keep them on the scorecard and interested in you during the interview! If they lose interest, you can forget about a good score.
Practice out loud the words and phrases you use to answer questions. Practice your elevator speech.
Have a great answer to the question why you?
Have questions for them that relate back to the job and help you to sell yourself. Don't waste time on questions that could be answered with a little research. Your questions should help show your personality. Give them a vision for working with you!