Umberto Eco: Rules for Writing Well

I found a series of instructions on how to write well on the Internet.
I make them mine, with some variation, because I think they can be useful to many, especially those who attend writing schools

Avoid alliterations, even if they’re manna for morons.
Don’t contribute to the killing of the subjunctive mode, I suggest that the writer use it when necessary [Subjunctive in English]
Avoid clichés: they’re like death warmed over [Dictionary of English clichés]
Thou shall express thyself in the simplest of fashions.
Don’t use acronyms & abbreviations etc.
(Always) remember that parentheses (even when they seem indispensable) interrupt the flow of (your) speech.
Beware of indigestion… of ellipses.
Limit the use of inverted commas. Quotes aren’t “elegant.”
Never generalize.
Foreign words aren’t bon ton.
Hold those quotes. Emerson aptly said, “I hate quotes. Tell me only what you know.” [Guilty! It’s because of Twitter]
Similes are like catch phrases.
Don’t be repetitious; don’t repeat the same thing twice; repeating is superfluous (redundancy means the useless explanation of something the reader has already understood).
Only twats use swear words.
Always be somehow specific.
Hyperbole is the most extraordinary of expressive techniques.
Don’t write one-word sentences. Ever.
Beware too-daring metaphors: they are feathers on a serpent’s scales.
Put, commas, in the appropriate places.
Recognize the difference between the semicolon and the colon: even if it’s hard.
If you can’t find the appropriate expression, refrain from using colloquial/dialectal expressions. In Venice, they say “The patch is worse than the hole”.
Do not use incongruent metaphors even if they seem to “sing”: they are like a swan who derails.
Do you really need rhetorical questions?
Be concise; try expressing your thoughts with the least possible number of words, avoiding long sentences — or sentences interrupted by incidental phrases that always confuse the casual reader — in order to avoid contributing to the general pollution of information, which is surely (particularly when it is uselessly ripe with unnecessary explanations, or at least non indispensable specifications) one of the tragedies of our media-dominated time.
Accents should not be neither incorrect nor useless, those who do make mistakes.
Don’t apostrophe an indefinite article before a masculine noun.
Not even the worst fans of barbarism pluralize foreign terms.
Don’t be emphatic! Be careful with exclamation marks!
Spell foreign names correctly, like Beaudelaire, Roosewelt, Niezsche and so on.
Name the authors and characters you refer to, without using periphrases. So did the greatest Lombard author of the nineteenth century, the author of “The 5th of May.”
Begin your text with a captatio benevolentiae, to ingratiate yourself with your reader (but perhaps you’re so stupid you don’t even know what I’m talking about).
Be fastidios with you’re speling.
No need to tell you how cloying preteritions are [telling by saying you are not going to tell].
Do not change paragraph when unneeded.
Not too often.
Anyway.
No plurale majestatis, please. We believe it pompous.
Do not take the cause for the effect: you would be wrong and thus you would make a mistake.
Do not write sentences in which the conclusion doesn’t follow the premises in a logical way: if everyone did this, premises would stem from conclusions.
Do not indulge in archaic forms, apax legomena and other unused lexemes, nor in deep rizomatic structures which, however appealing to you as epiphanies of the grammatological differance (sic), inviting to a deconstructive tangent – but, even worse it would be if they appeared to be debatable under the scrutiny of anyone who would read them with ecdotic acridity – would go beyond the recipient’s cognitive competencies. [Ecdotica]
You should never be wordy. On the other hand, you should not say less than.
A complete sentence should comprise.