Man Up Your Little Brother

Get him laid

As your little brother is young and retarded, he probably thinks that sex should be "meaningful" and only between a man and a woman who "love" each other and that you should "ask" before you "stick it in" and all manner of other socially-constructed bullshit.

It's up to you to teach him the truth.

Your little brother deserves to know: (A) how to get laid, and (B) the consequences of getting laid. There is no better way to accomplish both these goals than to take the bull by the horns and get the boy's feet wet. Except, replace "feet" with "dick." I'm not saying you need to teach the kid every little thing about sex -- that could be awkward -- but make sure he knows why he oughtta use a condom (a baby will end your life quicker than a bullet), how to meet women (get rich and act like a dick), and what sex means on an emotional level (nothing). If you need to rent a prostitute for the kid, do it. If you'd prefer to take him to a club and act as his wingman, that's cool, too (and probably healthier in the long run; you wouldn't want the poor kid to be addicted to whores by age 13). 

Just make sure the kid gets laid before he's too old, so he doesn't waste a bunch of time looking for the "right woman" to lose his virginity to. 

Get him drunk

You need to get your kid brother drunk while in your care not just because it'll put metaphorical hair on his chest, but for simple safety reasons. You need to be around him, sober, the first time he gets drunk mainly so he doesn't do anything he'd seriously regret later on, and so you can find out what sort of a drunk he is.

If it turns out he's a really fun drunk, or a horrifically angry drunk, then this is information that will be useful to him in the future, and should only be discovered in a controlled environment. If you find out little Jimmy is a ridiculously horny drunk and he starts halfheartedly humping the couch at home, then that will do significantly less damage to his reputation than if he'd gone to a high school party and tried to date-rape a cheerleader after his first Budweiser.

Additionally, preteen life can be kind of a bummer; getting him drunk early will teach him how great life can be, along with how painful and nauseous and stinky are the consequences to that sort of fun.

Pass on your role models

In the same way that you cannot get better at chess without playing a smarter player, you cannot become a better man without respecting and understanding better men who came before you. As a big brother, you will undoubtedly have racked up more role models than your younger sibling, so it's up to you to pass on the most important ones, and keep him away from the role models who just plain suck.

Make sure he likes Batman rather than Superman. Make sure he understands that Bruce Willis is better than Vin Diesel. Show him a few Robert Mitchum movies, a few noirs, some war movies, and a few dozen westerns. By the time this little kid hits puberty, his ideal vision of manliness better be Clint Eastwood, not Ben Affleck. Once your kid brother has a solid, acceptable vision of what a man should be, he'll be much better equipped to become that sort of a man. 

It'd be helpful to start here, of course.

Treat him like shit

In between all of the helpful stuff you should do for your brother like getting him drunk or laid or educated, you need to treat him like a smelly, worthless pile of shit. Insult him, beat him up, and generally do whatever you can to toughen him up and/or emotionally scar him. If he gets brought up experiencing nothing but the pleasures of beer, sex, and movies, he'll be too happy; he'll become complacent and weak. The only way -- the only way -- to prevent this from happening is to make his life as unpleasant as possible, as frequently as possible.

It might seem cruel or unfair at first, but understand that every dead-arm, every homophobic insult, and every bit of out-and-out abuse you hurl at your younger brother will turn him into a better, stronger man. The less likely he is to remain happy and content at home, the less likely he'll be to turn into a whiny weakling who thinks he's entitled to shit he didn't earn. 

Repeatedly punching him in the stomach will achieve this desired effect. 

Be a badass

Whether you wanna hear it or not, you will always be your little brother's biggest role model. If the father of a family is the son's model for God, then the big brother is the son's model for what it is to be a man. With that in mind, lead by example: act with dignity and strength whenever possible, and clever evil when not. Get laid frequently, get drunk even more frequently, and practice what you preach as often as you can when in his presence. 

If you don't act the way a Man (capital M) should when around him, he'll also fail to listen to any of your advice; if he sees you open a door for a woman or something, he'll rightfully label you a hypocrite and ignore all the legitimate advice you hurled at him. 

In a way, maybe your relationship with your kid brother will be like a manlier, less shitty version of one of those awful "coming of age" feel-good movies, where an older person teaches a younger person something and they both become wiser people who learn something about what it is to be a good person. 

Actually, fuck that. Just teach him how to fingerbang a chick, chug a beer in front of him, and you've pretty much done your job.