How do normal people do it?

[forgotten_aria]

When you are in the situation where there is something you would like to do, but you're not sure you can do it with the quality that the situation warrents, what do you do? Do it anyway and wait for someone to tell you you're not good enough to be doing it? Not do it anyway? Ask for an opinion? Something else?

EDIT: I feel like it seems like I'm shooting down's people's comments. I'm trying to understand how things are different, not trying to shoot them down.