Powerful people speak slowly, clearly, and distinctly because they are important enough to be heard. Try to cover all important information in ten minutes but realize that you may be asked to speak longer. At the interview Arrive 15 minues early. Get youself ready to give a great interview. Have good shoes.
Good shoes impress many interviewers.
Have a neat haircut. Indicate that you are serious by taking notes with a pen . Have a friendly smile, use eye-contact and a firm handshake. Have an extra copy of your resume and references with you in case they are requested. Emphasize what you can do to aid the company.