Realize that becoming a Jedi is a path for only the chosen few. Much like the military's super secret Delta Force, you don't approach the Jedi Order; they approach you.
If you have contacts within the Galactic Senate, use them! Have your parents act as surrogates on your behalf for admittance into the Jedi Academy. If you're an orphan, then like orphans the universe over, you may have to wait for the arrival of a Jedi -- or better yet, Angelina Jolie.
Get any experimentation with the opposite sex out of the way. Dating is forbidden and we all know what happened to Anakin Skywalker when he got a taste for knocking boots.
And you thought the Honor Code at West Point was tough? Understand the list of "don't do's" is nearly endless. Being a Jedi is akin to having your parents looking over your shoulder. All the time. You are the walking anthesis of what some women refer to as a Bad Boy.
Listen to your Masters even if they talk in Zen riddles or with irregular sentence structure. Remind yourself that you are not on drugs when various species of the universe converse with you.
Don't be tempted by the Dark Side. Remind yourself that with all their power, Dark Siders don't seem to have any fun.
As an Apprentice, be prepared to be an unpaid, sometimes under-appreciated servant to your Master. He gets all the glory while you get all the lectures.
Don't use your Force powers unless absolutely necessary. This includes, but is not limited to: going to Vegas and playing roulette; discovering through mind control the contents within Area 51; and investigating what exactly Twinkies are made of.
Expect to never see your family again. Then again, for some of you never seeing Aunt Crazy or Poppa Pill-popper, this may be beneficial.
Resist the urge to play with your "lightsaber." It can lead to blindness.