Put yourself in embarrassing situations. Go to a karoake night and "sing" spoken word style, hopefully off key, the great part is this isn't hard for most people. Take the guitar to some kind of open mic night and absolutely bomb, make sure it's tuned wrong before even going on stage.
I can totally see your point and agree completely. My legacy is something I think about constantly.
When I die, I want to say "FUCK YEAH! Let's do that again!", not "Yeah I felt safe".