I have some experience reading posts like this.
It can be quite a task, but it's not entirely cryptic, (bad joke coming!) I use "IDA Pro for posters" so I disassembled what he just said. Please use a better english next time, I won't be around forever to help you @relax
XSS Attacks are targetted at the user surfing the web. They essentially attack the browser of the user, not the server that hosts the website. If you want to steal cookies, you'll have to output the cookie into an URL that will "eat it" (accept it as parameter). I won't be telling you how to do this, for this you should do your own research, enough I have done trying to decrypt your post.
You could also attempt to keylog the user, there are XSS-injected Javascript Keyloggers. Do a research on that too.
You could juwst go berserk and fuzz every input of a site and discover which one is not filtered, but is not advisable, there are automated fuzzers for such task. If you don't want to go installing and testing, just get the latest Backtrack and it's pretty straightforward.
Note to advanced users: before you go to flame me because of helping a novice like this, giving it all chewed for him... if it's really into him, he'll succeed. I am a believer that if persons don't have it within them, they are just unable to and it is away from your hands to help him/her. Thanks.