How do I prepare for an A-level French speaking exam?

As a foundation for the speaking exam, it's important to have solid content knowledge so that you have an immediate supply of points to make which come naturally, whatever question you're asked. You can find this information through research, such as reading French articles on the topic. However, there is more to the speaking exam than just content knowledge. For example, it is a good idea to have key phrase starters in mind which you can use in all topics and which allow for complex structures and grammar, such as 'Il faut que' which leads to the subjunctive and will get those extra marks which can be so important. 

A unique part of the speaking exam is that there's pronounciation to think about. It's therefore helpful to listen to French; I personally like listening to music or watching French films and news in order to get used to the language. Another helpful way of practicing pronounciation is by reading French aloud. This means you don't have to worry about the points you're making but instead you can focus entirely on your accent and way of speaking so that French comes more naturally to you, which takes away some of the stress on the day because you can then just focus on your points rather than worrying about whether you're pronouncing everything corrrectly.