3 bad mistakes good people make on LinkedIn

(MoneyWatch) Recently, this blog looked at the bare minimum job seekers need to do on LinkedIn to make it worth their while. And previously, we've offered tips on everything from picking your perfect profile picture to how to use the site way more efficiently. Hopefully, long-term disbelievers are at least learning a little about LinkedIn and the options available. But not all activity adds up to a better presence. Here are three common, damaging mistakes that even experienced users make:

You stall on connections or obsessively add people

You want to hit 50 adds, at a minimum. "Fifty is the magic number in terms of making professional connections and having access to second- and third-tier connections," notes LinkedIn's career expert Nicole Williams. But keep in mind not to go in the other direction, adding strangers or people with whom you're barely affiliated. This isn't a popularity contest. "When it comes to LinkedIn, your networking strategy is really about quality and not quantity," says Williams. Not sure whether to add someone? "This is about who you could actually pick up the phone and ask for a career-related favor," says Williams.

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You leave your skills section blank

This is a really common omission because it may not seem necessary at first glance. If you're adding people to connections in your industry, your skills are pretty implicit, right? The problem is that some employers in similar but not the same industry may search these skills for keywords. You don't want to miss an interesting opportunity because you didn't fill out this section. "If you aren't sure what additional skills to add, do an advanced people search to seek out what your competition lists," says Williams. This concept is like having access to your competitors' resumes, she adds: "This will help you stay on top of your game and see what skills you need to brush up on or learn."

Choosing the wrong photo

Of course, not using a photo at all is probably the most egregious mistake. "If you've gotten married or changed your name people might not necessarily realize you are the same Marissa Miller from NYU," says Williams. But a photo that is unprofessional (think drink in hand) or doesn't show you (like a pic of your cat or a scenic sunset) is almost as damaging to your branding efforts because it doesn't put a face to a name.

Photo courtesy of Wikimedia Commons user TomChen1989