So this is another way to get someone banned. (I searched for "How to get someone banned & getting people banned and no results were same as mine). So.
1. First of all make a trial account.
2. Create a character in the name of "[victim's starting letters name here]bank" e.g.if the victim's name is Arcimagess then your character should be Arcibank (I suggest not putting Arcimagessbank, it's too big)
3. Use any kinda of money making scam (I Suggest the "WTS Primal Waterx20" and you send only 1 primal water in the name of Primal Water(20) instead of 20 [Kinda everyone knows this] ).
4. If your scam works then get the money and send them to the victim via mail writing something like "rofl" or even nothing in it.
5. Delete the character.
So if your victim is a a kind of noob (And even if he is not) he will take the mail from Unknown and will think nothing about reporting it. Though, the guy that you scammed will report you (99%). When blizzards finds out that you sended the money to the victim they will think that he did it and 3-day ban him. You can do this again and again and again till the victim is actualy fully banned. (Takes around 6 3-day bans if i remember well).
Tested and it works. Please let me know if you tried it.
EDIT: Forgot to say that you should NOT tell the guy you scam the victims name. (By the way, make sure you don't make the victim a huge profit out of this :-O)