Change image with choice on order

On the order form, when you click on a variation, I would like to see the cover of that variation displayed. It doesn't change automatically, and the reader must click on the arrows to view the other available covers. I currently have two cover options (sexy and discreet) that I put in the variations. The sexy cover is the default. But if they click on the discreet option button, that should change the image to show that variation.