Cost per action/sale methods require that referred visitors do more than visit the advertiser's website before the affiliate receives a commission. The advertiser must convert that visitor first. It is in the best interest of the affiliate to send the most closely targeted traffic to the advertiser as possible to increase the chance of a conversion. The risk and loss are shared between the affiliate and the advertiser.
Hi, Jamie! Very good list. I needed something like this for 2018 so that I know what to target in the future blogs I create. As for now, I’m comfortable using SiteGround affiliate network and it’s pretty good actually. Their hosting service is pretty much the best considered its price. I’ve tried others but SiteGround stands out. I’ll also try new affiliate networks, something from the list you have just provided. I think Amazon is too saturated at the moment, and I need a better network. 2018 will be interesting indeed.
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Now, it’s time to plan out your show. If you’re doing an interview-style show, you’ll now want to start getting some guests involved. You can use your existing social network to reach out to people you already know or are connected with on Twitter or Facebook. You can also head to Medium or Amazon to find authors or experts on topics specific to your niche.
More and more companies and startups especially are embracing remote work—where you use online collaboration and communication tools to do your work from wherever you want. And you don’t have to be a 20-something hotshot designer or coder to reap the benefits of working remotely. Many remote positions are for customer support positions or other customer-facing positions that don’t require specialized skill sets.

Watch them. How are other content creators in your niche utilizing advertising? What types of ads do they use? What are they promoting? What do they talk about repeatedly (if you keep seeing the same affiliate product show up again and again, there’s a good chance they’re making good money from it)? If you see a product or service they talk about that jogs your memory and you can ethically promote it too, find affiliate information by the methods described above.

Starting a podcast, like making a YouTube channel or blog, comes down to telling interesting stories and building an engaged audience. I’m probably sounding like a broken record by now, but you need a niche that you’re interested in and there’s already a demand for. Come up with a list of topics you’d like to talk about and then search iTunes charts, Google Trends and other podcast research sites like to see what’s currently out there and popular.
What kind of commission do they offer? One-time commissions or recurring commissions? For example, many programs pay you one time for sending a customer. On the other hand, some programs like membership sites or SaaS (software as a service) programs will pay you a commission as long as the person you referred is a paying customer. Recurring commissions are great when you can find them!
Win-win-win. The advertiser wins because they only pay when a purchase is made (as opposed to the shotgun approach of paying to advertise to the masses and waiting for a small percentage to actually buy). The affiliate wins because they make money while providing helpful advice. The customer wins because they get a trusted recommendation for something they might not otherwise have known about.
As Todd Crawford of Impact Radius puts it: “Marketers will need to monitor their vendors and partners for compliance with the GDPR. Vetting relationships will be extremely important, as well as ensuring that each party and your company have the appropriate consents and disclosures concerning collection, tracking, and processing personal data of your customers. Intelligent tools will be key for monitoring the types and treatment of covered data. As 2018 nears, it is essential to ask your vendors and partners whether they are or will be compliant by the May deadline, and to provide supporting details concerning their compliance efforts.”
Mechanical Turk: Amazon's Mechanical Turk is a resource for doing human-intelligence tasks, or as the site commonly refers to them, HITs. You get paid a very small fee for any given HIT and you'll need a good deal of volume to make a substantial amount of money. But it is a resource you can use in your spare time to generate a small income online. 
Many of the advantages of Clickbank also come with their flipsides. Also because there is such a vast pool of products to choose from, there’s a lot of competition for affiliates, particularly with the better quality products that actually offer some genuine value to consumers. Unfortunately, novices are not likely to be able to compete with the long-established and high-powered affiliates who already dominate the search engine results.
Consider some other ways you could make money online or elsewhere. You could start a website, try your hand at creating videos or build your own products to sell on the Internet. Unfortunately, you're going to need a fair amount of expertise to make it in any of these areas, and if you don't have the know-how yet, you'll almost certainly need some intense training in Web design, editing or the like. 
CPA marketing programs pay affiliates when a specific action is taken by the referral or lead. Common actions include clicks, impressions, form submits, sign-ups, registrations, or opt-ins. Since Cost-Per-Action models don’t necessarily involve a direct sale (and involve more risk taking) the payout percentages are far smaller than they are in Cost-Per-Sale.