Social media is constantly being touted for its brand-building power, and rightly so. But many small businesses fail to reap the expected benefits from their investments of time and money in social media, largely because they haven't fully grasped the unwritten rule of social media marketing: It's not which tools you use, it's how you use them that spells the difference between profitable performance and lackluster results.

Like professional marketers, successful small business owners target their social media activities for maximum impact. While their competitors are adrift in a sea of tweets and blog posts, savvy strategists focus and fine tune their social-media plays. Consider three social media campaigns that generated big results through careful targeting:

1. When Denver-based Sword & Plough launched its business to recycle military surplus material into tote bags and related products, it had a bold idea and grassroots support, including a $6,500 award from Harvard's Pitch for Change competition. The firm's start-up financing strategy focused on building its network of contacts via social media as the springboard for a Kickstarter campaign.

(More on the future of Main Street: The booming future of collaborative work environments)

After an intensive 12-month period of sharing its story via Facebook, Twitter, blogging, and media contacts, Sword & Plough launched a 30-day Kickstarter campaign. Within 24 hours, it had raised triple its goal of $20,000; within a month, it generated $312,161 in pledges from more than 1,500 backers. One of the keys to its success: targeted social-media outreach to build support before the Kickstarter launch. Today, Sword & Plough has recycled more than 35,000 pounds of military surplus material, employs a network of veterans through its U.S. manufacturing operations, and has sold more than 5,000 products. 

(More on the future of Main Street: The amazing promise of electronic payments)

2. Little Passports has built a $5 million+ business by providing products designed to create a global travel experience for kids. In order to expand and attract venture capital to push its growth to the next level, the San Francisco-based firm decided to focus its social media investment on Facebook. They started small and conducted extensive testing to fine tune the message and design concepts. Only when the message and packaging had been perfected did Little Passports launch a major Facebook ad campaign. In six months, its monthly revenues rose from $130,000 to $700,000 and the firm tripled its customer base. Its targeted Facebook campaign, coupled with its impressive customer expansion, helped lay the groundwork for a successful $2 million venture capital infusion.

3. Sharpie, a company well known in the business community for its pens and markers, wanted to tap an underdeveloped market for its products: teenagers. To engage this target audience, the firm ran a Twitter campaign focusing on self-expression through creativity targeted at users with interests in music and writing. The campaign increased Sharpie's follower base by 600 percent and loads of people began using the hashtag "#Sharpie," making a positive, brand-building association with the firm's products and creativity.

(More on the future of Main Street: How mom-and-pop businesses can thrive in the 21st century)

The impressive results generated by Sword & Plough, Little Passports, and Sharpie underscore the importance of narrowing your social media objectives and outreach. Be thoughtful about your approach, think it through, and test and refine before you dive in. Once you've done that, and as you continue to plan or fine tune your strategy, keep in mind the "Four T's" social-media targeting:

Target your tools: Most media experts agree that for both B2B and B2C firms, the three social media sources that generate the most business leads, positive brand exposure, and customer contact are LinkedIn, Facebook, and Twitter. By focusing your activities on these three tools you can build a strong outreach foundation and master their usage: Tweets that include links and photos, for example, are 86 percent more likely to be retweeted. With a solid base, you can explore other outlets like YouTube, Tumblr, and Pinterest.

Target your time: Establish a regular schedule for posting new content to your social media accounts. Successful marketers leverage their time by setting aside two or three blocks of time daily and bundling their social media tasks. This minimizes the distracting, time-frittering aspects of social-media usage and ensures that product development and other high-priority tasks aren't short-circuited.

Target your timing: Studies show that posts are more likely to provide you with valuable exposure at specific times of the day: Just before and after the hour, and around lunch or dinner time, are prime posting slots. Most marketers also agree that Tuesdays and Thursdays are the days where your posts are most likely to receive attention, so high-impact messages should be delivered then.

Target your topics: With 750 million+ Twitter users and a billion Facebook users, finding a way to ensure that your tweets rise above all the cyberspace chatter isn't easy. When you post online, 85 percent of your content should focus on passing along valuable, fun, and timely content to your audience — and only 15 percent should directly focus on news about your business and its activities. A major exception: pop-up retailers and food businesses that depend on Twitter, Facebook, and other social-media tools to alert customers to their schedules. But otherwise, ask yourself before you post: Why would someone share this with their friends and family? And if you don't have a ready answer, think twice about posting it.