By Kim Thai, contributor

Thousands of companies have hopped onto the Twitter bandwagon, trying to find a way to bring in business (and hopefully, revenue) one tweet at a time. But it isn’t as easy to Twitter — especially for companies — as one might think.

For those who don’t know: Twitter’s a micro-blogging site that allows users to communicate with each other in 140 characters or less. Think of each “tweet” as a text or instant message — not really directed at anyone but visible to everyone. And those who want to follow particular people’s tweets can simply subscribe to their feed for real-time updates.

But don’t mistake it for a fluke: In the last year, Twitter traffic has multiplied almost 15 times over, with more than 37.3 million unique global visitors in May, according to comScore. And as tweeting becomes hotter, companies feel more pressure to join the social-networking tool in order to stay competitive. But many are struggling to understand Twitter culture and, as a result, their tweets can come off as desperate or inadvertently turn away potential customers.

So to help you avoid any Twitter faux pas and maximize your tweeting potential, here are five rules for using this social networking tool that’ll keep your company ahead of the competition.

1. It’s a two-way conversation

Know those annoying people who always talk about themselves and don’t listen to others? Well, don’t let that persona take over your Twitter feed. Remember to listen. Too many businesses are just blasting out press releases over and over again — or worse, have an automated tweeting system and wind up ignoring communication from their followers.

That’s the worst mistake you can make on Twitter, says Julio Ojeda-Zapata, social media expert and author of Twitter Means Business: How microblogging can help or hurt your company. “It’s like these companies are standing out on a mountaintop with a megaphone broadcasting how wonderful they are, but Twitter is an intercom, not a megaphone.”

To avoid this common mistake, use Twitter regularly, and consider assigning a specific person to tweet on a daily basis. This way, companies can follow users who mention their business, engage users through direct messages, and actually build relationships with followers, rather than inundate them with information.

2. Your Twitter and company voice should sound the same

Twitter may be a casual medium, but that doesn’t mean your company has to be casual about it. Businesses should do what makes the most sense for their brands, experts say.

The key? Make sure that your Twitter voice reflects your company culture, says Joel Comm, CEO of InfoMedia. For example, Zappos — a fast-growing, lighthearted online company that sells shoes and other merchandise — recently tweeted a quote from Pooh’s Little Instruction Book. Whereas for Discover (DFS), Twitter came in most handy for posts on consumer spending and financial resources for customers.

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Twitter is all about transparency, so it’s important to be authentic when you tweet so that your company’s personality — whatever it is — comes through clearly. Comm likens the Twitter experience to a water-cooler conversation: Being relatable and fun is crucial, but staying true to your company’s core values matters most.

3. Tweet to attract and retain customers

Twitter can boost customer service to a new level, as Comcast (CMCSA) found when it established a Twitter account specifically to handle Internet complaints and other technical service problems. In a recent correspondence with a customer on Twitter, Comcast tweeted the same questions a representative would ask on a technical support hotline and received answers via Twitter. But instead of leaving the customer on hold for hours, Comcast was able to identify the problem immediately and send out a technician.

Consumers are impressed — and often surprised — by a company that openly and directly addresses customer-service problems. Twitter allows businesses, big and small, to take that extra step whether it’s about complaints or simple product queries. For example, Take Zettler Hardware, the oldest hardware store in Columbus, Ohio, which fields questions on common plumbing problems on Twitter, often responding to photos uploaded on Twitter (Twitpics), and replies with recommendations for replacement parts and repair strategies.

This kind of instant and robust customer service builds loyalty that’s hard to come by through traditional methods, says Rodney Rumford, co-founder of TweetPhoto. “The biggest sin,” he says, “is being silent.”

4. Twitter’s just the first step

While Twitter should be part of any savvy company’s daily marketing, it’s only the beginning of a successful social-networking strategy. “Twitter is a way to get your foot in the door,” Rumford says. “It’s the start to building a relationship.”

For business-to-business companies, Twitter’s a great way to network. Author Ojeda-Zapata gave the example of Mark Palony, a marketing manager at the software company SoftBrands (SBN), who was looking to collaborate with German software giant SAP (SAP). Palony searched Twitter for SAP mentions and began following an SAP worker near his area. He initiated some sports small talk through tweets and — with continual contact — moved on to actual meetings. Palony now calls it his “single best use of Twitter.”

Tweeting, Ojeda-Zapata says, is like having drinks online. It can easily lead to drinks in real life, formal business meetings — and eventually, company growth.

5. Have fun and be creative

The very nature of Twitter — from its 140-character limit to its fervent followers — attracts users with a short-attention span, so the best tweets keep users coming back. Interactivity can be a great way to do that: Auntie Anne’s and Dairy Queen ask customers about their favorite pretzel dips or Blizzard flavors through tweets, while at Home Depot (HD), confused shoppers can tweet for help as they search the aisles for particular products.

Twitter’s GPS function can also point businesses in the right direction. Cupcake Stop, a New York cupcake truck company, tweets its location to customers as it moves throughout Manhattan, and Union Pacific (UNP) lets fans track a historic steam engine road-trip across America.

The experts agree there’s no right way to use Twitter, but with these strategies, you won’t tweet the wrong way. Time to start the conversation.