How can I organise my thoughts into a good plan?

Planning is vital to structuring an essay well, and you should always take 5-10 minutes out of your writing time to set out a quick brainstorm or bullet point list. For a longform answer, try the following steps:

1. Take a deep breath, and remember exam conditions are far from ideal; nobody's expecting you to produce a perfect essay.

2. Consider your question, carefully. Highlight key words. If you have a choice of texts to write about, now's the time to decide how best you can show off your knowedge (i.e. which texts are most relevant, and which do you feel most comfortable tackling).

3. Get some ideas down. The most stressful part of an exam is often staring at a blank page. For a spider diagram, try rewriting your question out in the middle of the page (regurgitating the question often helps ideas to flow), and make each 'leg' a separate point. If the question is regarding an argument (so, "How far do you agree with..." or "[Quotation], to what extent is this true for...", try structuring your plan so you're sure you have at least one point for either side (don't forget that counter argument!), and your ideas are coherent.

4. Read back over your skeleton plan, and flesh out with quotes, key words and further ideas. Before you know it, you'll have the main work over and done with. Writing an essay seems easy when you already have your answer in note form!