Give the definition for what a postulate is to the students. Some students have likely never worked with postulates before, so clarification is valuable for those students.
Be sure to emphasize that the postulates can not be proven. However, after being given the postulates and assuming they are true, we can ask “What can we conclude that follows from those statements?” The experiments performed can then confirm that the postulates are true.
Discuss each of the six main postulates with the class. At this point, many students have not ever worked with bra-ket notation.
If bra-kets have not been discussed yet, tell the class that bra-ket is a quantum mechanical notation used to represent the state that something is in. Mention that the heads and tails results of a coin flip could each be represented by a ket. The convenience of bra-ket notation usually isn't apparent to students at this time; assure them that it will become apparent as the class moves into describing quantum mechanical systems.
At this point, the fifth and sixth postulate will be more foreign than the first four to the class; emphasize that the final two postulates will be discussed in detail at a later point in the class.