1. Talking About Sex
Unless you’re Carrie Bradshaw, Dr. Ruth, or some similar, more current cultural reference (paging Dr. Kinsey), you should not talk about sex on Facebook, especially if you have co-workers, industry associates or potential clients on your friends list. Not sure if the wrong person will see it? See rule #5. When in doubt, save it for Happy Hour…with your real friends. You know, the people you actually talk to in person?
2. Talking About Your Hangover…on Tuesday
Too many Appletinis with the girls last night? Maybe shouldn’t have had that last pitcher during Monday Night Football? Don’t beat yourself up…it happens. Just don’t post it on Facebook. The wrong people will see it.
EXPERT TIP: Coffee disguises the smell of alcohol. Facebook doesn’t.
3. Posting or Commenting During Work Hours
In case you hadn’t noticed, Facebook tracks your activity. It’s really one of its primary purposes. If you post comments, videos, or any other non-work-related content during business hours, you’re putting your job at risk. I know, I know, it’s such a drag having your curmudgeonly old boss expecting you to actually work all day, but that’s how it goes. Don’t like it? Fine. Keep posting. It won’t be long before you’ll be doing it from your phone in the unemployment line.

4. Your Idiot Friends
Sometimes, it won’t even be your own fault. One of your friends might do something stupid like tag an incriminating photo of you in a bikini (you’re a dude, in this scenario) from that bachelor party in Mexico with the donkey… Or maybe somebody posts something on your wall about that party you went to last week when your boss thought you had the flu. Maybe they think it’s just good, clean fun because they’re either:

  1. Already unemployed
  2. Insensitive to your desire to remain employed and/or married
  3. Smart enough NOT to have coworkers as friends and/or set their own privacy settings correctly to protect their sensitive secrets

The problem is, these things can get posted without you even noticing. If you’re a once-a-day or twice-a-week Facebook user, there’s the potential for hundreds, even thousands, of people to see it before you have a chance to take it down.
5. Typos
If you cant get you’re spelling and grammer write, your going to look like a dumass. Weather now, or in the future, your going to loose credibility if your status updates look like there written by a 1st grader.
Seriously. Take the extra 30 seconds to check what you wrote. It’s a couple of sentences, not War and Peace. Tired excuses like, “Oh, I’ve always been a terrible speller” aren’t gonna cut it, anymore. YOU’RE ON THE INTERNET! Google it.
The bottom line is, be smart, and understand that Facebook is forever. The Internet never forgets. It is becoming common practice, these days, for companies to do social media audits, both for current employees and prospective candidates. Just assume they will see everything you’ve ever posted online. Maybe not today…but some day. So be careful.