Hmmm... I guess here's a few things I've picked up along the way:

Don't be afraid to fail, but do prepare for it.
Limits are there for a reason; find what yours are, keep to the other side of them, and recognize that they may change.
Always do your research if you want to weigh in on something, just because someone sounds right doesn't mean they are.
Mind your own business, the easiest way to complicate your life is to get involved in someone else's.
Respect is earned and not given, but that's a two-way street.
First learn to survive, then work to thrive.

That's a few things, hoping that helps.