How should I structure an essay question?

Old proverb: 'Essay is like a pearl necklace' ... Stay with me on this. When writing an essay it's good to visualise a necklace. The pearl beads are your paragraphs, they're where all your beautiful knowledge is shown off one self-contained point at a time. More importantly the thread is your Main Argument, without the main argument your pearls would be rolling all over the place. This argument is the first thing you state in your introduction and conclusion, it should be seen clearly at the start and end of every paragraph and felt throughout, just like a piece of thread strung through beads. I know this visualisation seems simplistic but when you're under time pressure having a really simple basic structure that you stick to is key. Your enemy is 'waffle' so keep your argument punchy and clear by constantly reiterating it.