Richard Feyman (1918–1988) was an American theoretical physcisist.

He had a technique for learning and conveying information that would involve him ‘explaining a concept to an eight-year-old’.

To be able to explain something so that an eight-year-old will comprehend it, requires you to have a deep understanding of the something yourself.

If it proves difficult to explain, go back and revise those parts until the eight-year-old understands.