Every single offer has many banner sets witch can effectively promote the selected offer. It's really up to you which designs you chose. You can also select the size of the banner. 



Point - Go to the Offer / Offer List 

Point - Select the offer you like and click on the "Detail" button.

Point - Click on the promotools.

Point - Select Banners and then Banners.

Point E - Select the banner design that you like. 

Point F - Select the suitable banner size and then get the code or download the image.