Check out Author Scott Berkun's essay on learning from your mistakes. Point one: Place yourself in situations where you can make mistakes -- but only interesting mistakes that you can learn from. He explains it this way:

Compare these two mistakes:

a) My use of dual part harmony for the 2nd trumpets in my orchestral composition for the homeless children's shelter benefit concert overpowered the intended narrative of the violins.

b) I got an Oreo stuck in my underwear.

The kind of mistakes you make define you. The more interesting the mistakes, the more interesting the life. If your biggest mistakes are missing reruns of tv-shows or buying the wrong lottery ticket you're not challenging yourself enough to earn more interesting mistakes.

Read the entire essay here:
» How to learn from your mistakes

:-D