The modern meme, especially in online communication, is, "write like you talk." Oh, brother.
There is a distinction between a conversational tone and sloppy writing. It's comparable to "business casual" versus "for heaven's sake, put some pants on!"
When talkin' to a bud, ya gonna be droppin' your g's offa words, but do you really want that sort of thing in your writing, which represents to the world your competence, your expertise, your perceived intelligence?
Sloppiness reflects badly on you and on your brand, so avoid these common slovenly habits:
This is not pinkeye, but it does make me see red. "It's OK to start a sentence with a conjunction." Yes, occasionally this is fine, but it's become an epidemic. Listen to a 6-year-old tell a story sometime—every sentence starts with, "Aaaaand …" Is that how you want your writing to read/sound?
Limit the times you use "and/but/or" to begin a sentence. It's invariably best to nix the conjunction if you start your sentence with an independent clause: "In the case of Boffo soap flakes, the packaging …" You're already guiding your reader to your next point, so putting "And" at the beginning just dilutes your writing.
Here's another instance in which a device intended to break up the textual rhythm for specific effect has become the rhythm—and thus has lost its oomph. Have a thought; convey it. You make your point more effectively if you don't present it piecemeal. Like this. (See? Now, that's how it's used properly.)
Random acts of punctuation
If you don't know how to use the more exotic punctuation marks—semicolons, em dashes, ellipses—then stick with periods and commas, and please learn how to use the latter. Here's a primer. Also, lose the exclamation point, unless you're quoting someone yelling, "Fire!" or something of comparable urgency or intensity, and never use more than one at a time. I mean it!!!! (See how silly that looks?)
Hyphens and apostrophes seem to perplex many "conversational" writers, among others. Again, if you want to get your point across, don't undermine it with wayward hyphens and apostrophes.
Hyphens generally do not belong in verb forms: "It's time to check in," not, "It's time to check-in."
Apostrophes are unnecessary in forming plurals. (Not: Apostrophe's are unnecessary in forming plural's.) They are used in forming possessives (Cary's grants, Jack's lemons, etc.), except in the case of possessive pronouns (yours, its, ours, hers).
When in doubt, leave hyphens and apostrophes out.
Faulty grammar and syntax
A common flaw lies in subject/verb agreement—notably when a compound (plural) subject is assigned a singular verb: Good grooming and hygiene is essential for a job interview. There are two subjects, so are is the proper verb to use. When a single entity is represented by two nouns joined by "and," it does take a singular verb: Research and development is an important part of our business.
A related problem is assigning a plural pronoun—they, for example—when the antecedent is a singular, nonliving entity, specifically a company. "Globbco has rolled out their updated version of the KXJ-3000." Nope. Globbco has rolled out its updated version—and not a moment too soon, I say.
"Whomever" has cropped up in the strangest of places, and it's usually used incorrectly because people think it sounds more elegant. There's nothing elegant about not knowing what the hell you're talking about. More often than not, "whoever" is the right choice, so again, when in doubt, leave the "m" out. Here's a quick video guide to "who" versus "whom."
Misspellings and made-up words
When I see "definately" or "supposably" in text (Microsoft Word right now is underscoring both "words" with a big "Huh?"), I wonder what the writer was thinking, or whether he/she was thinking at all. It does, though, give me fodder for my snarky Twitter feed—and for articles like this one.
Do any other sloppy writing habits drive you nuts? Please offer them as comments.