I'm kinda new to all this, and I have been starting to work on some stuff on PS CS2. I need to figure out how to add a one pixel border around the image.
Or sometimes with borders, you don't want them on the sides. So you can just make 2 rectangles, and put them around the edge of your sig. But usually they're a bit bigger than 1px
I highly recommend to not use 1px borders, they look bad and take away the flow from a tag. Like others allready said, just press ctrl+ and go to Edit>Stroke.