The image you can use in a Facebook ad is dictated by the size of the ad you build. The larger dimensions of Facebook news feed ads make it easy to choose images. However, ads that appear at the side are much smaller, so you need to make a careful selection.
The web is a visual place, which makes images doubly important. Think carefully about what the image you choose says. Does it help convey the message you want to communicate?
By Kerry Butters