Sold my first picture today and wanted to know where to sign and how. It is a stretched canvas print on a frame so there is no border.
Lot of different opinions on this. "Fine art" photographers usually leave room and sign on the matte. Portrait photographers have usually signed on the bottom right of the print.
Make it clean and neat and make your own decisions to suit yourself. It's your print so you can sign it where ever.
I'd also consider having some sort of stamp or logo on the back to identity where you are, and to perhaps stop copying, although you can't really copy a canvas.