Minimize distractions
De-clutter your space, or move to a location that is empty. Make sure you are in an empty room by yourself away from all the noise and other distractions, this can help you stay clam and focused.
Be Prepared
Have your resume and a list of questions to ask at the end of the interview. Your resume can be used to help you remember the things you would like to highlight about yourself. The questions should be relevant to the company and the job you are applying for. It lets the interviewer know that you are interested in the job and have done some research on your own about the company.