Every lesson has a price. Books, mentors and mistakes all charge different amounts. Pick wisely.

Knowledge is never free, though the currency varies. A book costs hours, a person who knows costs your willingness to ask and look inexperienced, an error costs whatever the error costs. The cheapest options are usually the ones requiring a little humility up front. Mistakes teach extremely well and they set the price themselves, and you rarely get to negotiate afterward.

Before you learn something the hard way, check whether somebody has already written it down or would tell you over coffee. Spend the small awkwardness of asking instead of the large cost of finding out. Save the expensive lessons for things nobody could have told you.