If you go to the main forum page and go all the way down to the bottom you will see the photo thread. Go in there and at the top of the thread there are "stickies" pinned that walk you through posting a photo.
I have always had the easiest time using photobucket. If you are tech savvy you can post from facebook or pics from your own computer. Being technically challenged, I have better luck with a photo hosting service.
By the way, photobucket is free.