Randy Litchfield has grown accustomed to change. The CEO of digital messaging firm (and PROFIT 500 veteran) Inbox Marketer Corp. has seen his business grow and evolve tremendously. "We began as an email service provider 12 years ago when email was the only digital channel, he explains on this week's BusinessCast. "Since then we've added mobile and social media."

And the changes haven't just been to keep up with changing technology. Recently, the 50-employee firm introduced Umpire, a messaging platform that's shifting Inbox Marketer's focus away from being quite so service-heavy.

"With Umpire, we're productizing what we'd sold as a service," explains Litchfield (who also happens to be the former editor of PROFIT). It's a big shift, but it's the right way to go to keep the firm's growth sustainable, he says. "With a service company, you're not as scalable as you'd like to be. You get a new client, you hire some people, so on and so forth. By productizing yourself you're able to serve many many more clients with the same number of people. We don't have to grow the premises or staff as much as we'd have to with a full service offering." For a company that's had to move four times in 12 years, that's a relief.

The core of Inbox Marketer remains unchanged: getting the right messages to the right people in the most effective manner possible. Litchfield acknowledges that's something a lot of companies—particularly small- and mid-sized enterprises—struggle to achieve.

But some simple tweaks can change all that—at least, when it comes to email marketing, the preferred method of many entrepreneurs. Litchfield says it's not difficult to get more people to click through, open and read your content. You just need to integrate the following two steps before you hit "send":

1. Test your content

"Testing is the single most important thing anyone can do," says Litchfield—and most people don't do it. "By testing, I mean testing different subject line or different content. Have a controlled test. Segment your audience. One gets Message A, one gets Message B. You'll almost always be surprised by the results."

2. Tailor your messages

In many cases, you'll have a reader base that's wildly varied; it may be made up of readers in different industries, in different regions or in companies of different sizes. "My advice would be to segment into a few basic segments," says Litchfield. "Target the content accordingly to those segments. That will almost always make opens and clicks improve, along with readership and retention."

For more of Litchfield's advice, listen to this week's BusinessCast.