Answer the question. What is the question? Put it in your own words.
Before you get to the answer – you need to be sure that you know what the question is. To analyse the title, underline key words. Write it out in your own words, ensure that you absolutely know what you are being asked to do. Identify the boundaries of your question – what is in scope, what is out of scope, what is relevant and irrelevant
The only reason you need to have a plan is so that you know what you are talking about. How you do your plan is entirely up to you. You might need to pretty much write the whole thing before you know what your argument is. You might use a mind map, or write a linear plan, or something in between. If you think that its all in your head, please try to get it out of your head in some way before you start writing.