First, start with a boy, because males are the ones who are really responsible for the truly awful violence in the world. This is why they have to be treated much better than they are, instead of as second-class citizens as is currently the norm.
Then, from the day he is born, physically and emotionally abuse him (actually, do it before he is born). Do this to him, in school, and in the media. Especially have his mother and other females do it. The men can also engage in it or not protect him,or in some cases, not be there at all.
Want to see two movies about abusive mothers and weak fathers? Try Born on the Fourth of July and Boogie Nights.
Continue it throughout his childhood. Emotionally and physically abuse and humiliate him. A lot. His parents can do it, and other kids, and, again, in the schools and in the media. Let him be immersed in it. Make him soak, indeed marinate, in the propaganda.
Do it though middle school. The kids there, especially the girls, can ignore, reject and humiliate him. Continue it through high school and college until he graduates.
Then, make sure there are no good jobs available to pay a middle-class wage. Impoverish them by making sure good blue-collar jobs are outsourced, and shut him out from white-collar ones with Affirmative Action.
Make sure there is no place to turn unless it’s prison or homelessness. Give them psychiatric drugs, aka murder/suicide pills.
Blame everything on them. Make sure leftist feminists says, “Men are responsible for all the problems in the world.”Shame him and make him feel guilty for things he was never responsible for.
Then sit back and watch what happens.
There is a very good chance that some of them will become serial killers, mass murderers, rapists, and abusers, almost all of it directed toward women.
Others will withdraw from women, marriage, and trying to sustain society and civilization. They'll make just enough to support themselves, with no surplus.
All violence, to the violent, is an attempt to achieve justice, no matter how warped it is, since to them revenge is justice. All violence is in fact revenge, an attempt to replace feelings of humiliation with feelings of pride, defined as self-respect, self-love, self-esteem.
The Greeks noticed all of this thousands of years ago, when they wrote that Hubris (originally defined as humiliating someone in public) was followed by Nemesis - revenge.
By the way, they considered humiliating someone in public so obscene they banned it from the theater. They knew what humiliating someone leads to (the word "mortify" means to "make dead" - to make dead inside, i.e., their feelings).
I'm not sure how much of us is genetic and how much of us is environmental - nature or nurture. That argument has been going on for a few thousand years.
But, clearly, we are the result of both.
All of us are born flawed. Some of us are born more flawed than others. But those tendancies can be activated by the way we are treated by other people and by society, which includes media and the schools. By humiliation, shame, hatred, contempt, disrespect.
James Fallows, the neurologist in the above video, says he has the brain of a violent psychopath. But he didn't become one because he had "a wonderful childhood."
Even though he doesn't mention it, he has a satisfying job that he enjoys and is clearly good at. I'm sure he has a lot of respect and appreciation/gratitude from others. I'm sure he likes what he does and is good at it - including making good money.
I do believe there are some ways to ameliorate these problems.
1) There should be all-boy schools with all-male teachers until 12.
2) Men should be hired over women, especially for high-paying jobs.
3) Single mothers should always have their babies taken from them.
4) In a divorce the children always go the father.
5) Get rid of no-fault divorce.
6) No alimony for women.
I'd settle for those six things. It'd be a better world, a noticeable better world, one with far less violence than the one we have now. And far less abuse, humiliation and disrespect of young boys, most especially at the hands of women.