You've heard it over and over: Social media is essential for preserving and enhancing your brand in today's market. So you tweet. You post on Facebook. You link on LinkedIn. And in your few remaining spare moments, you wonder whether you ought to be posting on Google Buzz as well.

You know that all this is important for your company, but you also need to spend time actually running your company. So you decide to take the next step and delegate the care and feeding of your social media presence to someone else. Who should that someone be?

Here are some considerations that can help you make the right choice.

Inside or outside?

Facebook had more than 111 million visitors in 2009, and chances are some of them were your employees. "We did a social media survey for a finance company with 42 employees," recalls Dallas Lawrence who heads the social media practice at Levick Strategic Communications. "Twenty of them told us that they regularly use social media and/or read online news." That company can likely find an effective social media representative among those 20 employees, he says. "Before you go outside the company, look inside at who you already have."

In fact, you may have one or more employees who would be eager to use social media on your behalf. That was the case at junk removal service 1-800-GOT-JUNK?, where Travis Dudfield, public relations manager, approached top management about a year ago, proposing that he add social media to his duties. At the time, he says, the company's leadership was aware of social media and saw its potential, but wasn't sure how to start using it. "I said, 'Let's give it a try," Dudfield says. "'I'll set up an account, find some people to follow, and see how this works."

Today @1800GOTJUNK has 1,583 Twitter followers and 1-800-GOT-JUNK has 570 Facebook fans. Some of these are customers who report how pleased they are with the service. "One woman loved what we did so much she posted pictures before and after we came. In the 'after' picture her car was actually in the garage," Dudfield says. "That's an interaction with a customer I never could have had otherwise." He's since passed the pictures on to others at the company and to its franchises. "That kind of thing is great for morale," he says.

Who controls the message?

There's no need to limit yourself to a single social media representative. If a formal or informal survey of your employees turns up a dozen people who are interested in tweeting and posting your company's behalf, consider inviting all of them to do so. "If you've decided you want a Twitter presence, you might ask each of them to give you one tweet a week with a link," Lawrence says. "They may all have different expertise that would all be interesting to your customer base."

Even when you have multiple employees representing you on social media, one executive, perhaps from corporate communications or public relations, should be responsible both for making sure the posts and tweets actually happen, and for a vetting their content. "You want someone who will give something a lot of thought before they post it," notes Steve Birnhak, CEO of Inwindow Outdoor, which creates promotional displays for its clients in urban unused storefronts. "Even though social media evolved as an outgrowth of friendships, you have to be very careful what gets posted from a business standpoint." Birnhak started out handling social media himself, but soon found the time demands overwhelming, and so hired the company's public relations representative to handle social media instead. He appreciates the PR professional's expertise about what to say and what not to.

"Remember that everything that gets posted lives forever as part of your online reputation," Lawrence says. "A mistake can have a devastating impact on your brand." On the other hand, he notes, "It shouldn't be a 10-step legal approval. If your company's nature is that everything must go through multiple approval processes, and it would take two weeks to approve a tweet, then Twitter may not be the right medium for you."

Can your social media representative make a human connection?

While it's important to keep tweets and posts in line with your company's image and goals, it's just as important that your social media communications show transparency about your company, and convey a human connection. "One mistake we often see is that a company assumes it must either be the corporate communications director or the CEO who posts on social media," Lawrence says. "In many cases, the CEO is the wrong person, because he or she isn't good at providing transparency."

"I think it's a red flag if someone has a sell, sell, sell mentality," Dudfield says. "Or if someone values metrics over human engagement. I believe there's nothing more important than creating that connection with another human being. If that's not your primary goal, then that's a problem."

He adds that human-to-human contact is especially important for 1-800-GOT-JUNK?, because of what the company does. "What we do is very personal," he says. "We go into people's homes, pick up their possessions and take them away. They need to trust us to come into their homes and engage with them on their turf, so we need to make a connection with people." And, he says, in the social media world, "People don't talk to brands. They talk to other people."

In fact, Dudfield says, he stopped automatic direct messaging on Twitter precisely so his followers would know they were always conversing with an actual human being. "I've been blown away by how responsive people are," he says.

Does your social media representative truly understand your company?

If Dudfield were hiring someone else to handle 1-800-G0T-JUNK?'s social media, he would look for a representative who understands the company as well as he does himself. "I'd want someone who has passion for what we do," he says. "It's about helping people get their space back, and handling their stuff with environmental sensitivity. You need to really appreciate the ethics and principles we operate by so you can speak with a voice that makes sense to our brand as a whole."

"A lot of top executives believe social media is a good job for an intern," Lawrence says. "But that's not effective at all. You shouldn't put an intern in charge of social media, just as you wouldn't have an intern handle your relationships with NBC or the New York Times. It should be someone who has a full view of your company's agenda."