First of all, especially in an exam situation, always take five minutes to plan. It does not have to be a detailed plan, but even bullet points will help you to stay focused.
In your introduction: Always say your overall answer to your question, do you agree or disagree. What are your main reasons for this – literally a sentence/ phrase. It is also sometimes helpful to state the strongest argument why. Do not go into too much detail in the introduction. Also outline what you are going to talk about, again, very briefly the names of the arguments you will cover.
Paragraph one
First sentence: what topic are you are going to cover, is it convincing? (This can be for either side of the argument, but remember to make it clear whether you support this argument or not. E.g. say "Some may argue that... if you do not personally agree with the argument. Or "Rationalism is a strong stance because...) Be clear and concise and make sure that everything would make sense to someone who had never heard of the argument before.
Then, outline the topic.
Paragraph two
Any criticisms/ flaws of the argument you just presented.
Paragraph three
Can these criticisms be overcome? If so, how? To what extent can they be overcome? E.g. it does not completely refute the original argument but does show potential flaws or these criticisms completely refute the original argument. Is the original argument still strong?
Repeat the structure of paragraph on, two and three for another one or two topics (depending on the time that you have)
Conclusion
Re-state your overall argument and reason why. What’s the most convincing reason why? Never bring new information into a conclusio Make sure your conclusion and introduction fits with your essay. E.g. Don’t write about how all the arguments for Empiricism are flawed during your essay (and the criticisms cannot be overcome) and then say that Empiricism is the strongest stance. This may sound obvious, but in an exam situation it is easy to forget.