Gather experience... Look at what you should not look at. A feeling of anxiety is the sure and certain evidence that you should do this.
“Show me a poorly uniformed troop and I'll show you a poorly uniformed leader.”
“Nowadays, people don't ask you how you are, they say, 'Are you busy?' meaning, 'Are you well?' If someone actually does ask you how you are, the most cheerful answer, of course, is a robust 'Busy!' to which the person will reply 'Good!'”