[petercooper]

Here's what I'd tell my 21 year old self. I say this as a 27 year old who now knows he doesn't know it all but knows enough to realize what bits he got wrong:

Listen to your gut, all the time. Tell the truth to a fault. Find one thing you could be #1 at. Hammer at it. Keep doing it. Act like you're the best but don't talk crap about it. Act big and talk small. Be quick to accept criticism humbly, then be quick to ignore it if you know you're right. Things always change, things always get better AND get worse, and things are really never as great or as bad as they seem at the time.

My big regret has always been listening to other people and ignoring my gut feeling. Two years ago I "knew" in my gut buying property was a bad idea, kept saying "what goes up MUST come down", and enough people wore me down saying that property "never" goes down that I felt like an idiot NOT to buy.. now we know how that ended up ;-) I still listen to other people's bullshit, but I no longer give it credence unless my gut is willing.