Phone interviews are most often used as a preliminary screen. When preparing for the interview it's important to consider:
Tone of voice - ensure you're enthusiastic and use positive language;
Stable telephone connection - if using your mobile charge it fully before the interview; or better still use a land-line.
Location - find a quiet place for the interview, where you will be undisturbed by noise or others..
Notebook - ensure you have written down the points that you would like to share with the interviewer and take down information shared by the interviewer.