This post was originally published by HootSuite CEO Ryan Holmes on the LinkedIn Influencer blog. Follow Ryan on LinkedIn:

Social media can impact how and where we spend our money. More than three-quarters of US consumers, for instance, report that their friends’ social messages directly influence their buying decisions.

But the challenge here for businesses is that you can’t influence a social media audience you don’t have. Companies can post on Twitter, Facebook and other networks all day long, but that effort amounts to little without significant social followings on the receiving end.

Many businesses in this position, however, may be overlooking a crucial resource that’s already on their payroll: their own employees.

A company’s own employees represent an untapped, internal social marketing army. A little math reveals the potential. Let’s suppose a mid-sized company new to social media is able to gain an audience of 1,000 Twitter followers on its corporate account: significant but perhaps not the critical mass needed to drive sales. Now let’s suppose that that same company has 100 employees, each of whom has an average audience of 100 Twitter followers. If all of those employees share the company’s updates, the potential reach is now 10,000 Twitter users—a ten-fold increase.

At a larger company, the gains would be even more dramatic. (Think of a Fortune 100 company with tens of thousands of staff, for instance.)

Of course, your employees should never be obligated to share company social media updates from their personal accounts. This kind of sharing should always be voluntary. In fact, that’s part of the reason it’s so powerful. Organic, word-of-mouth messages from friends are often seen as more trustworthy than social media blasts from corporate accounts. When employees share messages, in other words, companies not only expand their social media reach, they also generate more trust and engagement.

We’ve adopted this approach in my company from the beginning and learned some key lessons along the way:

Lay the groundwork: Empower your employees on social media, with some proper training.

Encouraging social media use at the office—not banning it—is a critical first step. Yes, Twitter and Facebook can be a distraction. But they can also be powerful business tools. A recent McKinsey study, for instance, noted that social media use in the office has the potential to unlock $1.3 trillion in value potential for companies. The notion that Twitter and Facebook are merely for sharing vacation stories, selfies and food photos is increasingly dated and limiting.

But merely encouraging employees to use social media is not enough. At my company, every new employee is required to go through social media “basic training” in his or her first few weeks. We are, of course, a social media company and this kind of rigor isn’t necessary in every context. But social media isn’t something that employees should be expected to just intuitively “get.” The potential rewards of using it right and pitfalls of using it incorrectly merit some form of training or instruction. We’ve developed online certification, for instance, where employees complete a series of interactive modules at their own pace.

Set up the accounts: Give employees freedom to have professional social media profiles.

Once employees are up to speed, updates can be shared in several ways. One option is to have employees set up special social profiles linked to the business. At my company, for instance, many of our 650 team members have Hootsuite-affiliated Twitter accounts (with handles like @HootPeter or @HootMarc) and regularly retweet our messages.

Others choose to simply share our messages directly from their personal accounts. This obviously won’t work everywhere. But at companies where brand identity and employee identity are closely aligned, this kind of sharing often happens spontaneously.

I want to emphasize again that employees should never be compelled to share messages. What we try to do is surface interesting content that we think will resonate with our staff, giving them the option to share it out. Ideally, this is a two-way street: By sharing relevant updates, our employees help us while also building up their own social followings and reputations within their professional sphere.

Make it easy: Create company-approved updates employees can choose to share.

A key to tapping employees for social media marketing is to make the process direct and dead simple. How? Alert employees when you have important news to get out via social media, and pre-craft messages to make it easy for them to share. I’ll offer an example to illustrate.

Last year, a thousand job hopefuls turned up at our headquarters to apply for 100 open positions. The lineup of applicants went out our front door and around two city blocks.

This was no accident: In the weeks leading up to the fair, our HR team sent out company-wide emails explicitly asking anyone interested to help spread the word through their own social media networks.

These emails contained pre-approved sample Tweets and short shareable blurbs for Facebook about the upcoming event. With just a few clicks, members of our staff who opted to participate were able to share this news with their own followers, extending our reach well beyond office walls.

Effective social marketing depends on cultivating a sizeable and loyal audience, which can be a significant challenge and expense for businesses new to the medium. Yet, in many cases, employees at these companies already have a ready audience to tap into. By enlisting willing employees (and willing is the key) to amplify relevant messaging, businesses can instantly—and often by orders of magnitude—expand their reach on social media.

For more social media insight and to learn more about my company, follow HootSuite on LinkedIn.