What are the terms of the program? Is there anything I need to be aware of that would make a program not worth it for me. For example, Amazon Associates does not allow you to put your affiliate links in emails. If your main method of communication with your audience is via email, Amazon might not be a good fit for you. Wayfair, for example, does not allow their affiliates to post affiliate links on Pinterest or any other social media site. If that’s a strategy you rely on, Wayfair might not be a good fit for you.
The problem with affiliate marketing, like many other home business options, are the so-called gurus and get-rich-quick programs that suggest affiliate marketing can be done fast and with little effort. Odds are you've read claims of affiliate marketing programs that say you can make hundreds of thousands of dollars a month doing almost nothing ("Three clicks to rich!"). Or, they suggest you can set up your affiliate site, and then forget it, except to check your bank deposits.