Important things to know about women (verified by experts on the subject):
PMS - Just don't bother trying to reason with them when under the influence of this. They might kill you for it.
You can try all you want to understand them, but its never going to work. For some reason they feel just as baffled by our gender. According to two authorities on the subject (my wife and her best friend sitting behind me) women are just as baffled by other women. So its thoroughly hopeless.
If its furry, with wide-set big bulging eyes and a small nose, its "cute". Many things are "cute". Accept that women understand it and you probably don't.
If they want you to agree with them, don't because it's probably a trap ... unless they want you to disagree with them ... which is probably also a trap. You're just not going to win. Learn to say "I'm sorry." even when you have no idea what the hell is going on.
Under no circumstances ever, ever, ever agree with a woman who says, "I look fat in this, don't I?" They like to fish for compliments cuz they all seem to think they're fat and ugly and have no pride in being either (even if they aren't). This can also be a trap.
"Flowers seem like the perfect gift because they are pretty and boring like most women..." -- Red vs Blue -- Women will bore the crap outa you except for the fact that you might think they are hot. That's one of the great and noble truths in life.
Women are attracted to what they cannot have. Gay guys are the ultimate, partly because they have so much in common with them. They are also likely to dress nice, spend ridiculous amounts of time on their skin and hair and nails and everything else ... women's programming detects this as a likely rich and successful man (see the next item).
Women are greedy - so looking rich and wealthy is sexy. Well dressed, nice car, nice hair, nice everything ...
Many women are attracted to the bad boys. They don't know why, and we don't know why, so just accept it.
Teenage girls are borderline crazy more often than not. If you can get good at interacting with the crazy teenage ones, you'll thank yourself for it later when they are a lot more sane.