Ok lets get into it.
Im going to start off with a sig that i have all ready made, But im just going to show you how to make a pop out signature in this tut.
Open a background, or create a new one, im using a 500x150 background that i've already done
You can also use this link to find easy editable pictures.
http://photobucket.com/albums/y132/UG_renders/?start=01 - Find a picture you want to pop out, make sure it has a complete white background, or a solid color background so you can do this easily, and cut it out without much frustration. I'll be using this picture.

2 - Grab your magic wand tool and click once anywhere in the background of your image then hit Ctrl+shift+I to select just the image and it should select around your image.
3 - Now(ctrl+c) to copy, and (ctrl+v) to paste into your signature.
4 - Ok your image may be a little big so lets transform him (ctrl+t) your sig size might be diffrent so you can size him diffrently but make sure to hold shift while your using free transform.
5 - Ok you may notice some solid spots that wernt removed when you used the magic tool so just grab it again and click on the spots that shouldnt be there then just delete them. Now that you have your image cleaned and transformed and everything we can start our pop out.
6 - Go to Image - Canvas size, and follow exactly what i've done in my image here.
Your sig size might be diffrent, so you might need to use diffrent dimensions, but you should get the basics. Meaning basically if u want your image to pop out at the bottum of your sig then just change the arrows opposite to what i have done.

7 - Thats it basically you should be right to go, if you wish to get rid of excess stuff then just the polygon lasso with no feather and start cutting out the pieces you dont need or dont want to pop out.
This is a simple one i did.

Make sure you save your work as .gif file so that it will be transparent with the forum's backgrounds.
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