We might not buy this but according to the folks at Salary.com here are the: 

11 Social Media Mistakes You Don't Even Know You're Making

11. Not Getting in the Game

Some people are so afraid of damaging social media mistakes that they avoid the whole scene altogether. But that can be costly too, as social networks have become prime recruiting territory. Therefore, skirting potential issues via non-involvement removes you from too many opportunities to make that a smart option for most. At the very least, maintain an updated business profile on LinkedIn. It's the first place many employers go to check you out, and if you don't have a LinkedIn profile it likely sends the message that you're not current. If you’re in a creative or sales-oriented field, use personality to your advantage with at least selective involvement on Twitter, Facebook, Pinterest, Instagram or Google+. 

10. Having Retweet Regrets

Be wary of the quick click.You know better than to open an "OMG! Is this really you?!" link. But retweeting or sharing posts you haven’t actually read is risky as well. Headlines rarely reveal the whole story. If you're an online influencer, your audience counts on you to be a valid source of information. So before you attach your reputation to an article or photo link, make sure it’s what you think it is.Sharing a poorly written or error-ridden article -- or simply one that misrepresents your actual views -- puts you in an unflattering light. 

9. Lackadaisical Social Efforts

Rather than try to be everywhere at once, be selective with your time and network choices.Having a profile is like turning on a porch light. Non-responsiveness -- "Sorry! I never check that account!" -- sends a message. You may inadvertently communicate a lack of follow through or a lack of respect. Similarly, an account with outdated information and an old photo, or even worse -- a grayed-out avatar -- indicates half-hearted involvement. Your public profiles should display energy and professionalism, not tepid indifference. 

8. Painting an Inaccurate Self-Portrait

Read your story as shared on your timelines. When the tweets and sentences are strung together, who have you revealed yourself to be? Your life on the Internet has a theme. Make sure that your public information is balanced. If your story is punctuated by frequent happy hours, personal woe or is obviously self-focused, that will be the heading under which casual observers (and potential/current employers) will know you. Only your nearest and dearest (or creepers) will read every posting. So, check your timelines frequently to be sure you are maintaining an overall balance of the You that you wish to share publically.

7. Using Poor Grammar & Spelling

Many unfortunate communication errors can be blamed on autocorrect, but we do have veto power over our phone or tablet’s word choices. "It’s" does not equal "its," and "your" is an entirely different word than the contraction "you’re." Verbal shortcuts and misfires can look a bit sloppy. While "u" might save a couple of seconds when texting a friend, it’s probably better to stretch your fingers toward "y" and "o" first if typing "you" into a Facebook post that could be found by the HR guy who interviewed you last week. The bottom line is grammatical and spelling mistakes make you look bad. So do your best to avoid them.

6. Being Offensive/Inappropriate

Ah the fine line on social media between being yourself and not making everyone else uncomfortable. It's a moving target, invisible at worst and moving at best. You can do what you can to control who sees your posts by double-checking those privacy settings and using care with political, religious and sexual comments. An ill-advised joke or offhand comment could tag you with an unintended and unfair bias if seen by the wrong person.Consider who might potentially see your words. Before you click "post," think about your boss, your co-workers and the next company for which you hope to work. By exercising a little common sense, you can build your case rather than sabotage your chances.

5. Not Choosing Your Friends Carefully

Forget about trying to control the people who follow you, and focus on one thing you can definitely control -- who you choose to follow. Don’t friend, follow and collect contacts indiscriminately. Haphazard hoarding is ineffective and tends to cheapen the solid contacts you make. And the more unknown -- yet public -- contacts you add, the more you open yourself up to negative associations. It’s flattering to be chosen, but in the end it's not a popularity contest.

4. Failing to Keep Secrets

Be savvy and aware of social media check-ins that might reveal details your company would rather keep under wraps. For instance, broadcasting your visit to a competitor’s client might hurt the company's chances for securing new business. Similarly, on a personal level, checking in to the spa on a "sick day" or sharing your affinity for a competitor's product over the one you're selling, smacks of deceit and disloyalty. Besides, do your coworkers really need to know where you're going to get liquored up or the Foursquare check-in of the public restroom you'll be getting sick in later?

3. Falling Victim to "Tagging"

Perhaps you've gone to great lengths to control every ounce of information that's on your page. Good job. The only problem is, your friends might still be able to sink your ship. If you are social media friends with some less-than-discreet people who go tag-happy after a couple of drinks or have a tendency to toss "inside jokes" out where they don’t belong, you need to protect yourself. In addition to asking them politely not tag you in potentially humiliating photos, you can also adjust your settings so that anyone who tags you in a picture has to ask for permission first. This will prevent those embarrassing pictures of you passed out at a bachelor(ette) party or the time you fell asleep and all your friends drew on your face.Also, it’s smart to search links to your name from time to time. Yes, you can (and should) Google, Bing and Yahoo yourself. Knowing what employers will find when they search for you will help you explain it during the interview.

2. Being Too Negative

Here's a hint: just because you think you're being clever doesn't mean everyone else does.Gut-check your clever comments to see that they do indeed come off as "clever" rather than silly or snarky. Be engaging and encouraging of others. Your online showcase should include the successes of colleagues, not just promotions of your own. Avoid negatives, particularly rants against companies and products. Aim instead to praise good service and to query (rather than condemn) the questionable. Show yourself to be honorable and thoughtful. It counts more than you know and enhances your character and reputation

1. Never Engaging in Real-Life

Turn those virtual connections into coffees and lunches. A face-to-face meeting turns you from a faceless computer entity into an engaging and intelligent, real-life person. And, more importantly, a potential asset to corporate contacts.  We're not saying you need to set up face-to-face appointments with the hundreds (and possibly thousands) of people who follow you. But it's never a bad idea to handpick a few people you want to impress and set yourself apart by creating mutually beneficial relationships that go offline from time to time.

SOURCE: http://salary.com/11-social-media-mistakes