Yeah, that's right. People have been asking, so I'm pleasing :]
I made a tutorial on how to make my sigs. You may try them out, but be warned.
This tutorial is a total bitch.
(all done on a new layer moved to the top of all your other layers)
I make a box (using the rectangle tool) on top of the sig, that covers the edge of the top of the sig. Then I go to edit>stroke selection (make my foreground colour white) and set the number to 10, and press ok. Then I do the same to the bottom. Then I make a border using the rectangle tool around the signature, set it to 1 and press ok.
After I do all that, I lower the opacity of that layer until I see it looks good.