How much time do you think Jesus spent in what we call sermon preparation? Do you think Jesus studied as an average pastor studied? Do you think he read, did research, prepared outlines and so forth? How much time do you imagine Jesus spent preparing to teach?
By the way, the most common message in many churches is about this question: how can we know we will go to heaven when we die. Jesus rarely talked about that. He mostly talked about the kingdom. Think about that for a bit. When you are finished, keep reading.
I imagine Jesus’ mind was constantly churning with the question: how can I communicate with them about what the kingdom is like? Every time he saw some birds or observed a farmer or went to the temple, he was thinking about how to communicate the message of the temple.
When he taught, many times, he just taught. No outlines. No alliterations. No three points and a poem. He just taught.