Social media offers marketers a once-only-dreamed-of opportunity for free consumer-to-consumer advertising. But success depends on consumers being willing to share messages with their friends and followers, and often, they only share messages they like.

So, how do you get someone to “like” your ad?

The key, according to marketing expert Purush Papatla, is to post content that taps into already established consumer behaviors.

A professor in the Lubar School of Business, Papatla is studying how brands can harness the “liking” in social media to enhance sales. In another study, he and a colleague, Associate Professor Amit Bhatnagar, have probed how the “like” culture affects traditional advertising. They hope to tease apart which aspects of human psychology apply in both and which don’t.

“In social media, the microphone is no longer in the marketers’ hands like it is in traditional mediums,” Papatla said. “So marketers are scrambling to try to get some of that [message] control back.”

In the case of Twitter, he said, the decision to retweet or not hinges on whether the benefits outweigh the time invested by the social media user. In a recent study, he found Twitter users were most likely to share content that they believed would make them look good to their followers, or offered something their followers could use or that could start a conversation.

So how do lessons about consumer “liking” behavior inform more traditional advertising? Papatla and Bhatnagar collaborated to examine that question and uncovered a strategy that could save advertisers money.

Using customer survey data from a major automaker, the researchers determined how to boost products’ likability in various traditional ad formats.

They discovered that when consumers like one kind of ad for a particular product, that feeling spills over into other ad formats for that same product – especially if each medium focuses on a different product trait.

Their findings raised questions about the conventional approach to integrated media campaigns, which calls on all formats to deliver a consistent message.

But the results didn’t surprise Bhatnagar, who noted that each channel has distinct advantages in appealing to consumers’ emotions. “TV is best at conveying energy, ingenuity is online’s strength and print ads trump the other forms on warmth,” he said.

Using them together means brands can produce more sales with less advertising.

Next, Papatla is investigating how marketers can more effectively harness “likes” on Instagram, where 55 million images are posted every day, to boost sales.