Hi,
With telehphone interviews there are a few things to look at. First of all, through the application you may have answered certain questions such as:
'name a time when you lead a team', 'name a time during work experience or whilst at University that you had to solve a problem' or 'describe a time when you experienced change, how did you handle this?'.
If you've answered small essay type questions like the ones above, then they will ask you about your answers to those (usually asking you to evaluate). In addition to this, they'll ask you about certain things on your C.V., such as tell me more about this situation or could you shed a little more light on what volunteer work you've done etc.
The best thing to do is just be prepared on whatever information you've given/know your C.V. and make sure you are briefed on what the company does. I'm not talking extreme in depth detail, but just make sure you know the basics and how you'd fit into the bigger picture.
Just remember that during these telephone interviews - find somewhere alone, free from distraction, free from interruption etc. The worst thing would be for the interviewer to be asking about what's going on in the background! Also, the interviewer won't be out to get you. I've found in the past that they're usually quite enjoyable people to talk to, but make sure you speak clearly and answer the questions directly.
Someone said to me once that apparently a significant amount of those that get up, get ready and dress for work and then do the telephone interview, score higher than those that answer the phone in their PJs and do the interview that way. Dressing smarter can put your mind into a different mindset, and automatically make you more confident.
I hope that has been helpful, and I wish you the best of luck with the interview!