With many, many thanks to the Something Awful Forum goons, I'm pleased to present a selection of a few pages worth of the Tips And Tricks For Life Megathread:
If you cover up the tragus (http://en.wikipedia.org/wiki/Tragus_(ear)) with your finger, you can actually drown out loud background noise (concerts, traffic, etc.) and hear conversation much more clearly. This may seem a bit similar to the advice above, but it's not that obvious, and it's pretty useful for flirting at loud parties. Just don't be too quick to grab her head.
Fellows, when on a third date, never embarrass a third party. In undergraduate, I always saw a lot of guys who, while out on a date, would act out to get their date's attention. Obviously, this kind of behavior is gross, but it's also pretty insidious. If you're out with a girl, and some drunk kid wanders up to you,don't be condescending, just friendly and -if necessary- concerned. Trust me, even if it's a real zinger, save it. You'll only look like a bully.
People who are nice and polite are becoming more and more rare these days. Because of this, being nice is an extremely easy way to stand out from a crowd. If there is something you like about somebody, or there's something nice you have to say about them, don't hold it back.
You can save on your water usage by placing a jug of water in the tank of your toilet.
Also, don't write about illegal things you do on social networking sites. E.g., a guy from my school has been collecting (read: stealing) letterboxes and selling them. Mine recently went missing. Later tonight: Vigilante Justice. More on this later.
Hold each foot under the water before you step in the shower and you won't feel the cold of the shower floor.
Drink before you go out drinking. Consuming copious amounts of alchol at the bar gets expensive fast. If you spend a couple of minutes at home first you will save yourself an easy 20 bucks a weekend.
Keep your word. Following through on things is a great way to prove your integrity. That said, don't confuse politeness with honesty, and don't be afraid to get assertive. Don't be a dick or anything, just be straight up and don't let your personal biases affect your ability to lead.
And finally, for now, MysteriousLeg:
Look people in the eyes. Have a strong handshake. Learn how to speak intelligently but don't be pedantic. It has been said, but make an effort to see or talk to your grandparents more, they're going to die soon.
Web 2.5, bitches.