1. Unless your pronunciation is particularly poor, don't waste time on pronunciation lessons. It is much more beneficial to spend the time acquiring a good range of vocabulary and structure.
2. This is easy to say, but don't be nervous. Think of is like this: if you are really nervous and can't speak then your score will be poor. If you are confident and speak freely, you will have no idea what your score will be - it could be great!
3. Remember your job is to give the assessor something to assess - if you only say 'Yes' or 'No' during the interview, the assessor won't be able to give you a good score. Your job is to give the assessor as much as possible to consider. This means speaking as much as you can. Don't go off topic and don't talk about anything that comes into your head, but speak as much as you can. The assessor will stop you when he is ready.
4. Remember the assessor won't prompt you to speak. If you don't say enough he/she will go onto the next question. If you continue not to say enough, the interview could be very short!
5. Don't ask the assessor what questions mean. All he/she can do if you don't understand is repeat the question. You can though ask the examiner to repeat a question if you are not sure you understood it.
6. As with the writing test, don't show off. Some candidates see the interview as a way of showing the assessor what you know. They use sophisticated vocabulary and difficult grammar without really knowing how to use both. The result will be a decline in how well you speak and your score will go down.
7. Extend your answers by giving reasons:
a. "I don't really like going to the cinema."
b. "I don't really like going to the cinema because it's expensive and I don't like crowds very much."