2. Encourage feedback.
Followers of a company's social channels may also make a good sounding board for testing out the viability of new product concepts. Jon Olinto, co-founder of the fast-casual b.good burger chain in Boston—the company, with more than $10 million in annual revenue and 13 locations in New England, is known for using locally sourced meats and produce—regularly reaches out to constituents on Facebook, Twitter and email to get feedback on items the company is thinking of launching.
When b.good posted a new smoothie recipe that used agave syrup as a natural sweetener, it elicited several responses from Facebook fans highlighting health concerns about the way that some agave is produced, prompting Olinto to swap it out for another ingredient.
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The firm is also working to eliminate Coca-Cola products from its restaurants and replace them with more homemade drinks and soda from companies like Maine Root, which uses non-GMO ingredients. The move was overwhelmingly well received on b.good's social media channels. "The sample size wasn't huge—out of 250 comments, 248 said, 'Go for it and get rid of Coke,'" said Olinto, noting that the response prompted more intensive customer research (via an emailed survey). "But that actually means something to us, that maybe we were doing the right thing for our customers."
3. Exploit the negative.
The biggest mistake small companies make when it comes to interacting with customers on social media: Ignoring—or, worse, deleting—negative comments. "That's a knee-jerk reaction; it's putting up a wall between you and your customers," said Liz Jostes, co-owner of Eli Rose Social Media. "It's saying, 'I don't want to hear from you, and I'm not trying to solve your problem.'"
Olinto sees negative comments as a way to convert a customer. When someone complains via Twitter or Facebook about service at b.good, Olinto or his marketing manager responds as soon as possible, apologizing publicly. The company then tracks down the person's email address—direct-messaging the person via Twitter or asking a Facebook follower to send it along—and emails them a digital code the customer can redeem in-house for a free burger or drink.
Kyle Cassano, co-owner of Sacramento Marketing Labs, a digital marketing agency, said that responding publicly in a thread "is almost as valuable as reaching out to the person."
4. Choose your battles.
No matter how meaningless or mean-spirited a negative review may seem, it still warrants a response. Big issues—things that relate to a company's overall brand or reputation—require a direct response like a phone call or email, said Don Sorensen, founder of Big Blue Robot, which helps firms improve their online reputation. "The last thing a company wants is a firestorm of back-and-forth arguing over an issue."
But if the feedback is on a smaller scale—a problem with shipping or a minor product defect—it's "fine to address those directly in social media," Sorensen said.
For people who complain about small things like sauce flavors, AJ Bomber's Sorge sends out a quick apology and ends the conversation. "One of the most difficult things for me to get my hands wrapped around as [my company] has grown is that everything I do isn't for every customer," he said. "There are some things people just don't like, and that's OK."
For particularly fiery Yelp reviews, Humanele.com's Tillotson recommends quickly researching the commentator; if the person has a history of complaining against other companies, engaging in a heated exchange of words in a public domain like Twitter—which reflects badly on a company's image—it isn't worth anyone's time.
"The general rule is to just leave those alone," said Sorge. "Don't feed the trolls."
—By Maggie Overfelt, Special to CNBC.com