The full Punctuation Guide has its own page here.

Punctuation Extract:

The Apostrophe
Used to indicate possession:
1) With nouns that do not end with s, add an apostrophe and s.
women’s rights
‘It is a man’s place to rule, and a woman’s to yield’. Sarah Ann Sewell, 1869.
2) With plural nouns ending in s, add only an apostrophe.
teachers’ duties
N.B. With the exception of ‘one’s’, possessive pronouns (its, hers, his, theirs, yours, ours, whose) NEVER have an apostrophe because they already indicate possession.
The dog wagged its tail (not it’s).
It’s = it is!
The man whose tie has gravy on it (not who’s).

The Semicolon
Use a semicolon between independent clauses that are too closely related to be written as separate sentences.
‘There are two ways of disliking poetry; one way is to dislike it, the other is to read Pope.’ Oscar Wilde.

The Essay Writing Guide has its own page here.

Essay Writing Guide Extract:

Do make sure that you understand the question! You need to understand every word of it, particularly if there are terms which you may find familiar but be unable to define; for example: caricature, didactic, irony, satire. If in doubt, head for a dictionary.
Break down questions into blocks. This helps to structure the essay and makes sure you deal with each part of the question (see examples below).
Jot down all relevant ideas, references and quotations. Take each of the ideas and try to think of one other relevant idea, reference or quotation.

The process of writing essays is not dissimilar to that of a trial: a lawyer is trying to convince a jury and you are trying to convince your reader. A lawyer structures his / her argument around the evidence, as you should. You give ‘evidence’ in the form of quotation and close textual reference and quote ‘expert witnesses’ in the form of critics. In his / her summation, a lawyer will remind the jury of the most convincing pieces of evidence and give a clinching point.

Avoid unsupported generalisations about a writer or a period. ‘The Romantic period was one of political upheaval’is true but without supporting references it is a simple assertion rather than an argument. If you write, ‘As Baker points out, the Romantic period was one of political upheaval, including riots over the price of bread, the shadow of the American War of Independence and the bloody revolution in France’ (and footnote Baker), you are providing an authoritative reference, together with some brief examples of the kind of political activity you want to discuss.