Figuring it out your own way

Joan Feynman died recently. She was the younger sister of Richard Feynman. In "Surely you're joking Mr Feynman" he mentions some advice he got from her:

During the conference I was staying with my sister in Syracuse. I brought the paper home and said to her, "I can't understand these things that Lee and Yang are saying. It's all so complicated." "No," she' said, "what you mean is not that you can't understand it, but that you didn't invent it. You didn't figure it out your own way, from hearing the clue. What you should do is imagine you're a student again, and take this paper upstairs, read every line of it, and check the equations. Then you'll understand it very easily." I took her advice, and checked through the whole thing, and found it to be very obvious and simple.

Whenever I come across something that I find difficult to understand I remember this advice and try to figure it out in my own way. Sometimes I make embarrassing mistakes but I learn better this way.