You can put up banners on your site, to promote your affiliate offers. Most affiliate programs will usually provide their own creatives when you sign up for their offers. All you have to do is insert the banner on a highly trafficked page (your affiliate tracking is usually embedded within the code). Banner ads in the right locations can do a great job of driving sales.
How much will you make? I think my best month with Google AdSense was almost $5,000 over the last ten years. That amazing month blew my mind since it was actually near the beginning of my blogging journey. When you go from making zero to $5,000 in a month, that will rock your world. For me, it also got me even more excited because I knew there were other ways to monetize.