Not being prepared - Make sure you find out in advance exactly who will be interviewing you and how long the interview will last. A little research into the company and the people will make for a more relaxed interview experience.
Not rising to the occasion - Try standing during the interview and dress well; you may feel and sound more confident and animated.
Not verbalizing - You may be used to droning on to your friends over the phone but this won’t wash in an interview – make sure your responses are clear, concise, and succinct and that you make yourself audible at all times.
Not being confident - You may not be sitting across the table from your prospective employers, but always keep in mind that you’re the right person for the job on offer, so sell yourself as such.
Not using a landline - It’s essential you find a quiet room with a reliable landline. Lock the door if necessary and turn off your mobile.
Not listening to the interviewer - It may be harder to pick up subtle nuances over the phone so you need to pay extra attention to what’s being asked of you and attempt to decipher and reciprocate the mood being set by the interviewer.
Not knowing when to keep quiet - Remember, if you ramble on for too long, the interviewer will become easily distracted by their computer screen or by what’s going on out the window, so try to keep your answers to under one minute.
Not having notes to hand - Phone interviews provide you with a unique opportunity of having your CV, job spec, company research, and personal notes in front of you, so have them to hand and make use of them while you can.
Not preparing your responses - As with any interview, you’re likely to be dealt with difficult questions, such as “tell me about yourself” and “what do you feel you can bring to this company” – so, prepare and have your answers ready in advance.
Not asking what happens next - It is better to sign off by telling your interviewer that you are very interested in the position and by asking, what is the next stage?