I only beseech your wisdom about what mistakes/naivetes
I'll incur in my twenties
Strangely enough, a lot of the things you look back on as being "silly" from high-school, really aren't. From a certain point of view. You can only
truly live in "the now" and what seems important right now, really
is what's important right now. Not to sound fatalistic, but we're not guaranteed anything, not even to wake up tomorrow.
That said, probably the biggest thing I look back on my twenties and think "I was wrong about this" about is this: When I was in my twenties, I had no conception of just how short life is, and how quickly some opportunities can vanish. So I was too patient. I believed "patience is a virtue" (and in some ways it is) but I was probably too patient, too willing to take my time and "wait for things to develop." In retrospect, there are times when being more aggressive and forcing the issue is called for.
Like Bon Jovi sang:
Luck, it ain't enough, you gotta make your own breaks.
It's my life. It's now or never. I ain't going to live
forever. I just want to live while I'm alive ...
Sometimes you really have to say "fuck it, I'm making this shit happen and I ain't waiting."
The kicker is, there are still times when patience IS a virtue. The tough part is telling the difference. So if I had any advice for 20-something, it would be to think long and hard about situations and opportunities, do some "scenario analysis" and really consider when it's necessary to go balls out and go for broke and be aggressive.
I wish I could say there's an easy way to tell the difference, but even now at 37, I still don't know for sure. But at least be aware... You can't always just wait, wait, wait.