You get out what you put into it

If you treat it like a full-time or part-time job, you should eventually see a payoff. Hero Images/Getty Images

A common refrain from proponents of MLMs is that you can run your business in your spare time, and that the amount you earn is limited only by the amount of time you put in — the more you invest, the greater your return. In many situations in life, that advice absolutely holds true, but a survey from Magnify Money showed that most MLM participants actually earned less than 67 cents per hour, and 60% of all people involved with an MLM made less than $500 over the last five years. But this number may also reflect those known in the industry as "kit-nappers," those who sign up for an MLM only to get the starter kit of products at a deeply discounted rate.

But there are some people who do profit by running successful MLM businesses. So what are their secrets?

"Determine from the outset how much you want to make in a month — whether it is $200 or $1,000 — then set goals and do what it takes to get you to the income level you desire," said Edwards. That might mean dedicating a set number of days in a week or hours in a day for making calls and following up with customers. The point is that you have to set aside time for it, rather than just telling yourself you'll "get to it eventually."

Also, when it comes to selling your products, it's fine to start by approaching friends and family and others in your circle, but you won't find success unless you branch out.

"You certainly cannot grow a business on the backs of your friends and family, asking them over and over again to host a show or buy a product," Edwards explained. "If your goal is to make full-time money, you need to plan to invest significant time in introducing the business to others [which is also known as 'growing your downline,' or getting people to work under you, who you'll help manage] and selling products to make money."

Most people who sign up for an MLM are simply not willing to do these things, or cannot find the time, Edwards said. People who are looking for "easy money" when they sign up with an MLM are going to find themselves disappointed, but those who treat it with the seriousness of a part-time or full-time job should eventually see a payoff, she said.