Another type of rich media advertising on Facebook is a post of an image. This is one of the most popular types of ads ever since Facebook began favoring visual content. The optimal size for News Feed photo ads is at least 1080 x 1080 pixels, otherwise your image will get cropped. Adjust your image based on the target audience's needs and by what will appeal to them the most.
You also have the option to select a Custom Audience -- this allows you to target people on Facebook who are in your company's contact database, visited a page on your website that has a tracking pixel, or use your app or game. To learn more about how to set up a Custom Audience on Facebook, check out these instructions. (And for more on the specifics of these criteria, visit this Facebook targeting resource.) How to prepare and market using Facebook Ads