I am getting to the point where I occasionally sell a few prints to friends and family. I have been asked to sign and number prints, but I cannot get myself decide on a limited series. There is just no way I will commit to destroying my originals, at least not yet. So how do I number the print? "#13", "13/--", "13"? Signature bottom right, numbering bottom left? Sign on the mat or on the print? The latter would mean keeping a white border around the print inside the mat.