One good advice our calculus lecturer gave us was: "Proofs are not meant to be understood by reading them from beginning to end. They are usually meant to be `

One good advice our calculus lecturer gave us was: "Proofs are not meant to be understood by reading them from beginning to end. They are usually meant to be `checked` that way. Most of the time, I start reading the proof from the conclusion and work backwards. Often I write my proofs that way as well."