here are 2 different simple borders used by many ppl in their graphix..
first 1 (kinda 3-D)
1) make a signature/logo/watever
2) once you finish it, make a new layer and do Select > All or just right click and press Select All.
3) then right click, and press Stroke.
4) Choose the size of the border you want, and the color. then you have 3 options that says "Inside", "Centered", "Outside". Select 'inside'. and press OK.
5) now right click on that layer (on the little layers window at the right), and select "Blending Options". Put all the options you want, i recommend "Bevel & Emboss" and "Contour", and all the other things you want.
you're done!
2nd type
1) Do steps 1-3 of the first type.^^^^^^
2) When puttin stroke options, select size 3, color matching your signature, or just any color you want and "Inside" as well. press Ok.
3) Repeat again steps 1-3 from the first type.
4) This time select size 2, and color white and obviusly in "inside" again. press ok.
5) take the Magic Wand, very carefully select the white part of the border, and then press delete. *i suggest zooming in the image, so it's easier to select it with the magic wand.*
you should now have a 1 pixel border, and like a space between the border and the edge of the sig. somethin like this:

see the blue border? thats it.
if you cant get it done at the first time, thats natural. happened to me also, just keep tryin and practicing and you'll get it eventually.