How do I cite an image I found online on the cover page of my report?

If an image is used only as an illustration, please read the conditions for reuse beforehand.
There is no in-text citation, place under the image (or on another page):

Author, year (or n.d.). Copyright year, name copyright holder (or CC-license or 'In the public domain').

Also provide a reference entry for the webpage.

See also the video APA Guidelines: Images, from 0:35.