Smart companies use social media to connect with fans and customers. But even if you increase your Facebook Likes or Twitter followers, you'll always be competing with everyone else to get into someone's feed. And in the case of Facebook, you'll even need to pay to get eyeballs on your posts. Here's where the old-fashioned email newsletter--a free marketing channel--shines. That's according to Roman Khan, cofounder of Linjer, an e-commerce purveyor of luxury leather goods that recently blew past its Indiegogo fundraising goal due largely to doubling its email database before the campaign began. Here's how Khan says you can do it, too.

Compile an initial group of subscribers by tapping your personal networks.

Prior to Linjer's Indiegogo launch, Khan and his co-founder identified several hundred friends they knew would open and read their email newsletter. "If you're one founder, you'll probably be able to get 200 quality emails into your subscription list and, the more founders there are, the more you can get in," he says.

Amplify the list by holding a competition.

One way to orchestrate a contest involves posting a graphic on various social media channels, then sitting back to see what kind of results you get. A better approach: Use a cloud platform to automate and garner data that can help you make decisions mid-competition, such as doubling down on influencers who are fanning virality. Linjer used Gleam, a simple tool that gives companies a way to reward contest entrants for different types of engagement. You can offer varying numbers of points for signing up for a newsletter, following your company on social networks, and sharing on social media. The idea: The more an entrant shares, Likes, and follows, the greater the chance he or she will win a prize. "Competitions are a highly efficient way of getting people motivated to share your story and share your products across different channels," Khan says.

Offer a scarce prize that people actually want.

At the end of Linjer's five-day contest, it gives the prize of a limited-edition soft briefcase worth hundreds of dollars, a product that had garnered the most Likes and reshares on social networks. "The key here is to make a reward special. It shouldn't just be a generic product from your store. It should be something that's hard to attain normally," Khan says.

Give the most points for signing up for the newsletter.

You want to incentivize people for sharing your campaign across multiple social media channels, but if your intent is to expand your newsletter database, award the most points to people who sign up to receive your emails.

Pay Facebook $5 to $10 a day for the length of your contest to extend your reach.

By doing this, Linjer spent only about $0.06 per click to not only garner more Likes on the social network but also more than double its email subscriber list--going from 424 subscribers to more than 1,000. While these aren't huge numbers, Khan says 30 percent of the $50,000 Linjer raised on Indiegogo in the first 48 hours is a direct result of building its email subscriber list. "This is a really low-cost way for entrepreneurs to boost their traffic, grow their newsletter list, and grow a community around their brand," he says.