The best long-term advice I can give is that you have got to practice speaking the language as much as possible. Try to organise weekly sessions with teachers/language assistants/online tutors to get used to speaking the language and interacting with someone who is fluent in the language you are learning. Doing this can only improve your proficiency in the language, and give you confidence for when it comes to the real thing! Ensuring you listen to a lot of that language is also key when you are forced to improvise answers and are put on the spot. The more you are used to hearing the language, the better.In addition, I have always found that a sheet of notes are perfect as short-term preparation. For GCSE, you tend to know the questions you will be asked and the answers you’re going to give; a few key phrases that you learn off by heart are still very useful, especially in case your examiner asks you a question you haven’t seen before. For example: Sin embargo, Se suele decir que, No obstante, Que yo sepa, Es un tema delicado. These are just some of the phrases that will ensure you stand out in the Oral exam. Take the time to construct a sheet covered in useful words and tips for the exam; it comes in very handy in the days leading up to the exam/before the exam itself.In summary, I would advise that there are two key ways to prepare for the oral exam. 1)Get as much practice speaking the language as you can. 2)Write down key words/phrases and information that will help you stand out to the examiner; learn as many as you can off by heart.