Participate in any Kiwi farms, well, anything. I'm assuming you don't wanna be an asshole to people who will help you be an asshole to others, because of this, just join any dedicated raiding group, like the Kiwi cucks or something. If this is the path you wish to choose, it may be advisable to learn skills that help your douchebaggery, like accounting but for doxing. There is also hacking.
If you wanna solo gigachad it your way, then ig some shooter of sorts. That can cause a lot of pain to your victims and even more trauma to their friends and family.