There is no app for appreciation. It doesn't get much more low-tech than shaking a hand, patting a back, writing a note or just saying thank you.

But few activities measure up to the high-impact potential of recognizing and rewarding your hourly workforce – if you do it right. Otherwise, well-intentioned , yet poorly executed praise can backfire like a melted ice cream cake served the day after Employee Appreciation Day.

Chew on the 'Carrot Principles'
It seems counterintuitive that there are best practices - and even a science of sorts – for something as personal as recognizing employees. But that's the problem; sometimes recognition is as impersonal a hand-written note saying simply, "Good Job!"

Speaker and bestselling author of "The Carrot Principle," Chester Elton, has spun up something of a science around rewards and recognition ("Recognize effort, reward results.") Last month when Chester headlined Hire Minds, Snagajob's Hourly Hiring Summit, he laid out the bedrock requirements for making sure you maximize the effect of your praise and positive feedback.

Here are the three must-haves for making gratitude more than mere lip service, according to Chester:

• Frequency:You can never say “thank you” enough (As long as you follow tips No. 2 and 3 below). Trust me, if you do, someone will tell you.
• Specificity: General praise has no impact on people,” according to Chester. Walking around the office while glad-handing and spraying out generic praise fails to resonate whatsoever. Instead, let employees know why what they did was special, who took notice and how it impacted the greater company.  Make it personal.
• Timeliness: There is a very small window of time for maximizing recognition. And odds are if you have to preface praise with "Remember when?" or "I've been meaning to tell you," then you've already missed your chance. .

If you nail all three of these principles, you're likely to deliver the type of praise that resonates within employees for years to come.

The engagement pay-off
So why bother recognizing your workforce? Quite possibly, you're afraid that excessive, effusive praise or even rewards will go to their heads. And you're right – but not in the way you might have imagined.

Offering effective praise, recognition and rewards is the number one way to build employee engagement. And as study after study suggests, engagement has an immediate, dramatic and lasting impact on your bottom line. In other words, when employees are recognized for hard work and those above-and-beyond efforts, they're more likely to invest their discretionary effort into the company. When that happens, they're engaged. And a cycle of productivity emerges.

In a Towers Watson study of 50 companies over a one-year period, organizations with high employee engagement had a 19 percent increase in operating income and almost 28 percent growth in earnings per share (EPS). On the other hand, companies with low levels of engagement experienced a drop in operating income of more than 32 percent and an EPS decline of 11 percent.

That's right, taking the time to hone your appreciation around the proven best practices doesn't just drive profits, but failing to do so can be damaging to everything from turnover to frontline sales.

Once you're comfortable with the basics of making "thank you" more meaningful, raise your game. Realize that appreciation can be more than verbal or physical tokens of gratitude. Workforces – especially those comprising hourly employees – respond well to benefits promoting work-life balance, such as flexible work schedules. And don't forget to look beyond the worker and to thank the entire family with a gift card treat here and a bonus vacation day there.

What's the closest way to an employee's heart? Quite possibly though a chicken-scratched thank-you card and a 44-cent stamp. It may also be the closest way to hitting your business objectives.