A successful affiliate program will pay you a commission for each successful sale. You should consider how much ROI you hope to get, and whether your program will provide you with the ROI you need. Some programs will pay you by the click, while others will pay you based on the number of leads you generate. In the former case, you’ll earn a commission for each lead, but you have little control over the commission. A good affiliate program will reward you with a percentage of the sales made by your partners.