Adhering to the following guidance about usage, syntax, punctuation, style, and form will perceptibly improve the quality of your writing.
1. Use vivid verbs. Monitor your writing for excessive use of forms of “to be”—is, be, and their variants—and other helping verbs such as has, as well as other weak verbs like do and go, and replace with active verbs. Also, avoid baseline action words when possible. For example, people don’t just walk: They lumber, march, or stroll. Don’t strive to eliminate every instance, but do minimize vague verbs.
2. Reword or delete clichés. Think outside the box. There is no one-size-fits-all approach. All (fill in the blank) are not created equal. These. Are. So. Lame. (YMMV.*)
3. Always use the serial comma. When listing more than two things, include a comma before the conjunction preceding the final item. Omitting the comma can prompt ambiguity about the list’s organization, but inserting it never contributes to confusion.
Related article: The Rationale for the Serial Comma.
4. Avoid scare quotes. Generally, use “scare quotes” only to signal that the writer is calling out the quoted content as being dubious or ironic, not to introduce an unfamiliar term.
Related article: 3 Erroneous Uses of Scare Quotes.
5. Hyphenate phrasal adjectives. If a two-word phrase doesn’t appear in the dictionary as a standing open compound, it is not exempt from hyphenation. Exceptions can be made for terms of art (vocabulary specific to a topic or discipline and well known among one’s readership), but use this privilege sparingly, and double-check that open phrasal adjectives aren’t ambiguous or confusing.
Related article: 5 Types of Phrasal Adjectives That Require Hyphens.
6. When in doubt, don’t capitalize. If you’re not certain that a word or phrase should be capitalized, look the term up in authoritative sources. Writers often Capitalize Important Concepts that don’t deserve such emphasis, but careful writers don’t. (Also, for example, job titles are capitalized before a name but not after it, and generic terms that are abbreviated references to proper names—such as act when referring to a specific piece of legislation—are just that: generic.)
Related article: Avoid Gratuitous Capitalization
7. Refrain from using all-caps. Employ italics to emphasize a word or phrase. Reserve use of all capital letters for humorous indication of shouting or panic, and avoid in formal writing.
8. Be consistent in formatting treatment. If a caption is boldfaced or italicized or appears in a different font, all captions should be formatted that way. If top-level headings are capitalized headline style (Capitalized Like This) rather than sentence style (Capitalized like this), treat subheadings the same way.
9. Vary sentence length. A healthy mix of sentence length and syntactical forms (simple declarative statements, sentences with lists, sentences with subordinate clauses and parenthetical phrases, and so on) keeps the reader engaged. Lockstep sentence construction and consistently short or long sentences are distracting.
10. Manage paragraph length. The traditional five-sentence paragraph form is fatiguing. Strive to craft paragraphs that will, in published form, be about ten to fifteen lines in narrow columns or five to ten lines in full-width display, and, as with sentence length, avoid paragraphs of consistent length.
Related article: How Long Should a Paragraph Be?
If you decide to ignore or break a rule for effect, take care with the rest of your content, or your attempt at deviation may seem like simply the most egregious of your errors.
* Your mileage may vary.