You don’t necessarily have to have a huge site or lots of traffic. Consider emailing an affiliate program’s contact person (look for contact info on the site or in affiliate newsletters) if you send a lot of leads their way, rank well in the search engines for a related keyword or have a high conversion rate. Make your email compelling. Read my tips here. You just have to be a good fit and provide excellent value to the merchant. Another good resource for this is here.
If you're serious about making money online, start a blog. Blogging is one of the easiest and most sustainable income sources. As long as the blog is setup the right way, in the right niche, with the right content targeted at the right audience, and the offer is complementary to the content, you could make a tremendous amount of passive income from a blog.
Now, I know what you’re thinking. Most of the software and apps you use on a regular basis are made by massive companies or established development studios. Well, yes. But many successful apps, particularly those in the Apple and Google stores, are created and marketed by individuals and small businesses. In fact, independent developers made $20 billion in the App Store in 2016 alone.