Style is not something I can prescribe in a set of notes like this. Write well: if you have any problems in this direction, it is for your tutor to tell you about them. But here are a few random points instead.
Register
This is what linguists call a style appropriate to the occasion. Be aware: a certain scholarly gravity is called for. Not too heavy so that it's uninteresting. But avoid colloquial abbreviations: should not, not shouldn't. Jokes are hazardous: if they don't [do not follow my practice as regards don't] work, they can cost you a lot. Avoid them, on the whole: or at least don't be jokey. Don't for goodness sake imitate the way I'm writing here, either the rather flippant colloquial style or the somewhat overbearing tone, or the numbered subheadings. This is an essay on how to write a literary essay, not a literary essay.

Quotations
Firstly, quote sufficiently but not too copiously. Not more than a third of a (handwritten) page at the very outside, and usually just a few lines at a time. It's your thought, not the quotation, that is the point. On the other hand, never forget that your ideas should be tied firmly into the text, and that you should demonstrate this by quotation. Secondly, always give page numbers for your quotations: you will need to know where to find them again.

Short paragraphs
No short paragraphs.

Length
A non-assessed essay should be about six sides of handwritten or four sides of typed A4 at least.

Copy it
Always make a photocopy of any essay you do before you hand it in. Academics are very unreliable, and not uncommonly lose essays.

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