How can I ....

You can use any sort of editing software.  I think I actually made mine in powerpoint and then cropped it in Gimp, which is about the same as Paint Shop.  A lot of people make theirs in Paint Shop.  I am just not as comfortable in Paint Shop as I am in Powerpoint.  I think I then used Paint to shrink it small enough to put into my sig.....hope that helps.  Basically, you can use any sort of editing software that will do what you want it to....a lot of them are probably already on your computer.
 
Once you have it made, upload it to photobucket and then use their tag to put it into your signature.  Just be sure to make the IMG  in the tag all lowercase.

thanks. But what is photobucket? whats the IMG? and when i press open in paint to open another picture the one i have closes....howcan i open 4 pics?

I don't know how to open 4 pics in paint or if you even can.  That is why I resorted to Powerpoint which is a microsoft program that some people have.  I use this b/c when I save as I can save as a jpeg or a gif which are more widely recognized by other editor programs.
 
[linkhttp://www.photobucket.com]www.photobucket.com[/link] is a place where you can host your images.  You upload it to this once you have finished making the image what you want.  You will have to sign up for an account.  This is where you will get the IMG tag that you will copy into the signature area of your profile and then make the letters lowercase. 
 
I only use paint to make my images smaller by opening it then going to image, stretch/skew and then I usually make my image streatch 30% by 30% so I can upload.  I don't really use it for any other editing so I have no idea if it is capable of doing much more. 
 
 

thank you