I'll teach you how to take an image, and paint it on to a background with a nice grunge effect. And i'll go the extra mile and tell you how to make a sig.
1-Make a new document, 400 wide, 200 high (anything works, but use this 4now)
2-Open your image in a seperate window. (file, open, your image)
3-Have your 200x400 image open and selected, fill it with any color, not too bright.
Use a dull blue for starters.
4-Create a new layer above the colored layer. Keep it transparent.
5-Take a rough grunge brush, and the clone stamp tool, and on the image window, alt click a spot, switch back to the 200x400 window and start stamping.
6-Dont copy too much, and try to leave some blank rough spots.
7-Now you should have your grunged image on the transparent layer, above the colored layer.
You can stop there, because thats an easy way to extract images and put them into sigs and have it look nice, but you can do this to have a descent looking signature.
*8-Set the layer with the image to luminosity, and merge it down.
9-You should have a very monotone signature
10-Add your self a border, for simplicity sake just take the pencil tool, 1 pc black, and trace the edges while holding shift, and youl have a 1 px black line border.
11- Whalah, not too shabby. Heres what you can have, a descent looking sig.
-Keep in mind the point of this tutorial was not to make a good signature... but a bases for extracting images with a grunge feel. You can do alot using this technique.
It helps to have more content along with your image, and to have it blend smoothly.
Heres a little something, maybe if people like i can make a tutorial on how to make a good looking sig.
i used the same technique plus some techlines, and a few overlay layers, some channel editing to get this sig