Once you think you understand the question, write a one or two line interpretation in your rough work along the lines of “I think this question is asking……” This is for your benefit, not the examiners. This interpretation is something you can check bank on later on while you're writing your essay. Sometimes people get half way through an answer and forget what it is they are trying to do with the answer. This interpretation can help remind you what it is you're trying to do.
Another useful thing to do at this point is to write out in bullet points an outline of your answer in your rough work. You should include any relevant names and dates while you can still remember them. It makes a big difference to do your figuring out of which-point goes-where at this stage before you've written anything.
The end result of all this preparation is a much more impressive way of structuring your essay, giving it a definite direction, an argument. Rather than an aimless meandering around the subject, an essay that picks a target and moves in a straight line will keep the reader on board and make them think about the issues. Introduce the issues and what your argument will be, give evidence for your argument based on research in the area, draw a solid conclusion. This kind of argumentative essay requires clear thinking, preparation, and a concise (non-waffly) writing style. It is not very difficult to cultivate these things, it just takes some time and effort.
Writing your Introduction
Once you have prepared your answer, writing the introduction itself is very simple. The first thing your introduction should have is an interpretation of what the question is asking and a short explanation of how you are going to answer it. This is just a slightly padded out version of what you've already written in your rough work.
The Main Body
Structure