How do I sit an oral exam?

I am very sympathetic because oral exams are my least favourite part of my subject, even at degree level, and honestly the best thing to do is practise! Try talking to yourself in your head in French, try to find someone in class to chat with, or even use these sessions for extra practice. The more you speak it, the less nerve-wracking it becomes, and the easier it is. It's very easy to go in to panic mode and forget every word you've learnt, so having some idea of what you would talk about for each subject is a good idea, and learning filler phrases that give you some thinking time is also useful!