[font color=\'#000000\']Been asked and answered before, but...
I sign on the front below the image, on the right. On the left I write the title and print number. I use a black Pilot Precise V5 Rolling Ball pen. I mat my images with about a 1/2" 'show' on 3 sides and 3/4" on the bottom, signature edge.
My editions are limited to 200 prints--nothing bashful about me!--and I'm up to #8 on my most-popular image, Black Tree, created on Mr. Reichmann's fall-colors workshop in 2001.
This is NOT a way to make money! Said another way, a good way to make a small fortune in fotografy is to start with a large one.[/font]