(Without having a set question to give advice about!) It is important to begin by dissecting the question, picking up on the key terms to determine what the question is asking of you. Once you have done this you will know how you shall set about answering the question, i.e. Compare: requires your answer to provide insight into both the theories or concepts being questioned. I would then recommend you take 10 minutes to plan your answer fully. This will allow you to structure your argument and you wont be repeating yourself, providing the most efficient way to write your answer. Also, if you did happen to run out of time, your examiner can see your plan and will be able to take into consideration the thread of your argument.
Following this, you should plan an introduction to tell the examiner your line of argument, followed by the points you will cover. Then, using clear topic sentences, I would advise covering 3 points using the PEA strategy: Point, Explanation, Analysis, using case studies to back up your theoretical understanding, demonstrating knowledge, understanding and grasp of key terms. You would then conclude by summarising your points, drawing your response together by explaining the end point of your argument and potential future possibilities. This should create a structure allowing you to answer any question successfully.