When I really can't be bothered starting an essay, I set myself word limits, and then reward myself. So, 15 minutes on facebook/youtube for every 250 words, or each paragraph or something (this is my ten minute break since I've completed 5 of ten essay plans xD). You tend to loose a bit of the flow, but if you've made a good plan then it's not too bad, and especially if it's a requirement, at least you've got something on the page. The key to this is having a quiet space to yourself as well, without any distractions - don't do it with friends around or the TV on, you're too easily distracted.
My other advice is, trust your writing skill, and don't spend a lot of time perfecting one sentence of paragraph. If you tend to get anxious and need things to perfect, it can be relaly counterproductive because you spend a lot of time getting tiny bits right, instead of getting lots down and fixing it up later.
Finally, I know a lot of people, especially teachers, will tell you that your literature essay doesn't need to be structured, but if you're into formulas, you might find it easier to think of your essay as a formula, or use a template. For example, 'the author explores [theme/issue/contention] in [scene/character] by [technique/phrasing], for example [quote ]' Literature doesn't have to be creative, as long as you're getting your ideas down in a cohesive manner.
I don't know if that helps, but I hope it did
