How I Make a Full-Time Income in My Spare Time -- And How You Can, Too Affiliate marketing is simple, but it's not easy.

As a young man, I learned how to make money online, initially to pay off my mother's debt. I've used these same skills to create a lifestyle that many dream about, flying 96 times just this past year; living in such places as Johannesburg, Shanghai, Thailand and now Mexico, and speaking on stages all over the world. All because I've learned how to make a full-time income in my spare time with affiliate marketing.

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I believe affiliate marketing is the easiest way to build a business online, because you don't have to make your own product, nor build your own audience of people who want your product. Rather, find a product that already has a proven track record, that already sells, and market that product.

1. Find a product you can promote.

To begin, find a product you can promote as an affiliate. I prefer information products over physical products, because there is no production overhead or fulfillment cost, resulting in higher commissions for you. I recommend finding such products on sites like Clickbank.com, JVZoo, Share a Sale, Commission Junction or Peerfly.

I got my start on Clickbank, which organizes its products by category and ranks them by gravity, a score that quantifies how many affiliates successfully sell that product. As such, you want to choose a product with a high gravity score.

People buy information products for one of two reasons: in order to pursue a passion or solve a problem. Products that solve problems, what I like to call pain products, tend to be the most lucrative, because people are trying to solve a problem that is most likely affecting their well-being. One of the first products I promoted was "vertical leap" training to teach people how to jump higher in basketball. Then I started promoting potty training and erectile dysfunction products. Dog training is another lucrative market. Today, I'm in the business education niche, flying around the world teaching others how to start an affiliate marketing business themselves.

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2. Find your audience.

Next, define your audience. Determine who would buy this product and the pain it would solve. A great way to do market research is to look at the media kits of magazines and publications. For example, if you are selling a potty training product, the media kit for a parenting magazine will tell you the demographics of its audience. You can use that information to market to the very same audience. Another place to do research is in online forums your target audience frequents. Read through the forum's questions and answers to to get more information for your market research.

3. Send your traffic to a landing page.

Once you've defined your audience, then find a way to reach them. There are many ways to reach out to your target audience. Two good methods are through YouTube and paid advertising using Facebook. For instance, you can use Facebook ads and Facebook Audience Insights to directly target moms with toddlers and run ads to them.

In your ad, address the problem your audience is trying to solve, such as, in this case, potty training, and offer a video of your solution. Carefully select an image for your ad that attracts your audience's attention. From my experience with potty training, images of baby butts work! Always collect your audience's emails, so you can sell to them again and again. To do this, send your audience to a landing page, before redirecting them to the product's sales page.

In return for giving you their email, offer your audience what is referred to as an "ethical bribe," a free giveaway, such as a video which, to further this case study, shows you how to potty train your child in 30 days or less. The free video can basically be the Clickbank sales page for that particular product.

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4. Monitor your numbers.

Essentially, all that remains is for you to monitor your numbers. For every dollar you spend, you want to get at least a dollar and ten cents in return.

Run your ad to various segments of your target audience, all the while measuring which audience responds best. For example, if you determine the age range of mothers with toddlers as 25 to 40, you can then segment that list into two age groups, 25-32 and 33-40. Use your data to narrow your focus to the age group that responds best.

You can then further segment that list, and so on, until you end up with a target audience that is highly responsive to your offer. The more targeted the audience, the relatively cheaper the ads and the more money you make on the other end. You can also split test the ads themselves, once you have a responsive audience.

Keep a spreadsheet of how much you're spending on ads, how many email addresses you collect as a result, and how many of those emails convert. Once you get a handle on how much money it costs you to make a sale, the cost per customer, all that remains is to scale.

Know that, if you can make two dollars for every dollar you spend, you can make $20,000 by spending $10,000. At the same time, you're building an email list for that audience, to which you can sell more related products.

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The process of making a full-time living as an affiliate marketer is simple, but it's not easy. Most people are not willing to invest the hours to perfect each one these steps for maximum returns. Rather than do the hard work, they will switch products midstream, or get distracted by a shiny object promising to make them more money in less time. What they fail to realize is that even the shiny object that looks so good on the sales page takes work to turn into a profit.

Rather, develop clarity as to how much money you want to make. And then focus on the path to get you there. Listen, if others are profiting from the product you're selling, you can, too. Stay the course until you are profitable. Dial into your target market, either through content marketing, paid advertising or a combination of both. Collect your audience's email addresses, cross-sell them related products and keep track of your numbers. Once you can turn one dollar into two, do it all day long, and soon, you too will be making a full-time income in your spare time.