Writing an essay - whether it's for coursework submission or practice for an exam - can seem really really overwhelming sometimes. It's not as hard as it seems, if you know where to start though!
First, you need to look at what the task is and make sure you choose the right topic - it always helps to read through the mark scheme, so you can find out exactly what the examiners will be looking for in your answer. Writing check-lists and working with mind maps can be really useful; grab a piece of paper and note everything down that comes to mind about the topic, the themes and the context - everything you can think of!
Once you know what you're going to write about, the next step is to use all your ideas to structure the essay. This part really makes a difference - as soon as you have a sense of how your paragraphs are going to look like, everything will seem a lot easier! Think about it as writing a contents page for a book or a wikipedia article, but for your essay. First you'll need an introduction - what do you need to include in that? How about the first paragraph - is there a specific topic you need to start with? What smaller sub-topics can you think of? As you go through your check-list or mind map of ideas, you can begin to slowly cross them all off as you include them in your essay plan.
Now, that you know how your essay will be structured, it's a lot easier to know what quotes you need to look for, if there are any specific literary terms or examples, perhaps things about context that you need to look up.
Once you have all the information that you need, you will have to put all of that into sentences - the actual writing part. This can be tricky sometimes, but you can always go back to your plan to look for ideas and just try to explain them in your own words. And you're almost done! A couple of important things at the end: always always spell-check, make sure you answered the question, don't forget about your word count, and that everything you have included is relevant! That's it. I pinky promise, it always seems harder before you actually start doing it!