Question about keys

I have a feeling I might get global banned. I was wondering when you get banned, do you have to rebuy arma or do you just buy a new cd key and put it in steam? I'm new to hacking you see

Buy a new CD-Key, use a cd-key changer, change the key and then never launch the game by steam again and you should be unbanned.

(Launching the game through steam will re-assign the global banned key)