in a nut shell, you upload images, place prices of what you want to get, advertise your here, image wise they are all kind of crooked and really not my cup of tea. i won't say more than that because you didn't ask for an actual critique.
you'll need a lot more keywords and a description, some of the images are quite small like the one above. you'll want a description that is more than - the watermark won't appear.
---Mike Savad