1. First take the sig you are working on.
2. Now simple put a new layer on top. Fill it with black.
3. Grab the Polygonal Lasso Tool, hold shift, and make the border u like to have. (dont make it too fat)
4. Delete your selection. Now its time for the blending options xD
You need to change the following options:
Blend mode: Soft Light
Drop Shadow: Opacity 75% , Distance 3, Spread 0, Size 5
Inner Shadow: Opacity 65%, Distance 5, Choke 0, Size 5
Bevel and Emboss: Depth 1, Size 0, Soften 0
Stroke: Size 1, Opacity 50%
(and i also used a white color overlay on 5% because my border was too dark)
Then use your rectangular and elliptical marquee tool to make your border look nice (delete some figures out of it)
(As you can see i dragged my layer hue/saturation and color balance so it has color that matches the sig)
You should now have a border looking somewhat like this
(5. You can use the same blending options on the text)
6. Now finish your sig.
My outcome:
Regards,
Atari.2600