how do u create a pattern to add to a sig?

like little dots or straight 1px lines ?

Just look up some tutorials without scanlines and shit, they're not worth it..they're ugly.

New document > Design > Edit Define new pattern > Old document > Fill in

Make a new document the size of it will depend on the size of your pattern.
When you have created your pattern go to >edit >define pattern.
Then when you want it in your work you can go >edit >fill >then choose pattern and your pattern.
yay