1) Don't share your feelings. The only thing that should follow the words "I feel" should be "like a beer right about now."
2) Pee standing up. Though it's okay to pee while sitting if you're severely drunk and likely to fall into the urinal.
3) Don't make conversation at the urinal. Unless what you have to say is really, really hilarious.
4) Don't go vegetarian or (gods forbid!) vegan. Remember, those cattle, pigs and chickens would kill and eat you if they had the chance. Should we feel bad that we invented cattle guns?
5) With the exception of pizza, don't bake anything. If it can't be fried, grilled, or eaten directly out of a bag, then it isn't worth eating. Of course, if someone bakes it for you you can eat it, just pretend it came off a grill or out of a pan. We need our delusions.
6) Women are always getting hard on themselves and each other for their looks. Too bad they don't have more self esteem! But guys? We all think we're hot stuff, despite excess hair where we don't want it, lack of hair where we want it, and the extra beer-flab. It's because we can appreciate unconventional beauty.
7) We can appreciate unconventional beauty in ourselves--but ladies, don't try to convince us that strange looking she-beasts like Sarah Jessica Parker or Gwyneth Paltrow are hot. Saying it doesn't make it so.
8) While we appreciate our own unconventional hotness, we are completely unable to judge hotness in other men, so don't ask us to. Brad Pitt? Probably a decent actor, bagged Angelina Jolie, but we can't tell if he's better looking than Will Farrel.
9) Ladies, we will notice other women go by, especially if they're good looking or dressed scandalously. We can't help it, it's an evolutionary reflex. Any guy who pretends he doesn't is a liar. Stop dating liars. (However, we will try to not make it obvious--in return, don't make an issue out of it!)
10) Likewise, got cleavage? Showing some leg? Yes we will look, quickly--if you don't notice us doing it it's only because we've mastered the ninja-art of subtle deception. But if you don't like the idea of us noticing cleavage/leg, then you'll have to wear something less revealing. Like a potato sack. Sorry.
11) Women can look good in a pair of pants, but there's not a straight man alive who doesn't think a good looking woman looks better in a skirt. Just like there's not a straight woman alive who doesn't think a guy looks better without a harpoon stuck in his forehead.
12) No movie is ever improved with a tacked-on love scene, just like no rock album is ever improved with a sappy power-ballad. But every movie is improved with a tacked-on explosion.
13) Much as the American flag means to us, it could still be improved by adding a skull and crossbones, and maybe a flaming dagger.
14) If you ever meet a girl who is okay with playing "Ain't Gonna Bump No More With No Big Fat Woman" by Joe Tex at your wedding, then PROPOSE MARRIAGE IMMEDIATELY.
15) Bacon makes everything better. Don't agree? Then explain why you hate America, Hitler.
16) If you don't have chest hair, it doesn't mean you're not a man. It just means you're a lesser, more shameful man.
17) Guys Night Out (TM) is a regular, necessary event. It has its own rules, the only one I can share being that the First Rule of Guys Night Out is to not speak of Guys Night Out. Except here. And that the ladies should keep some cash handy for bail.
18) Ladies, if you present a man with one of your problems, then expect him to come up with what he thinks is a simple and obvious solution. Whatever you do, don't tell him why his solution is stupid and won't work, even if that's the case. You'd rather have someone not try and solve the problem, and just provide sympathy? Then tell your problems to a woman.
19) Beer is amazingly awesome and the ancients who stumbled upon inventing it deserve our constant gratitude. Proof of this is that the Trappist monks who were denied the pleasures of women have instead taken to brewing--and invented some of the best beer known to mankind. These monks knew they had to get pleasure one way or another.