How much time should I spend planning an essay in an exam?

As a general rule, longer than you think! Planning is often overlooked but it is essential for consistent, high-level answers: perfect your planning and you'll be set to give your best possible answer. For argument's sake, say you have an hour to write an essay. At least ten minutes (perhaps even fifteen) should be spent structuring what you are going to say, in what order you are going to say it in, and what your central argument will be. Rushing into answering the question because you are stressed about time pressure will likely lead to incoherent and poorly focused essays that won't be very impressive. Think of it this way: would you rather a clear, well-structured four-page essay that covers all the relevant points, or ten pages plus of all the thoughts in your head that don't really make sense when you read them through at the end? It often feels odd to not start writing your essay straight away, but planning is essential for success in exams and if you master it, the rest shoulnd't be too difficult.