Indeed, humor can be hard to handle. Many years ago in Toastmasters I gave a humorous speech that was merely a series of jokes with few connecting comments. To point out my error the evaluator mentioned a speaker who used jokes carrying numbers known to the audience. His punch line was all that the speaker really had to do was cite the number of the familiar joke and his audience was sure to laugh. Words were unnecessary.
A few years ago a humorist compiled a book of many jokes aligned to tell a logical story with a beginning, middle and end. It was a monumental work cleverly done, but it fell flat. It lacked soul.
Sometimes it is possible to use jokes in the public domain and alter them to make them appear as an integral part of the talk A simple example: “A man said to a friend—–.” The speech preparer could say “This morning my neighbor told me——–.” This will personalize the story and make it seem more original.
An absolute “no no” is opening a speech with a joke or a wry comment that has no relation to the speech, speaker, or listeners. Such a speaker believes that he has to have a joke for the sake of the joke in spite of its irrelevance.
As we can see from these awkward comments, humor takes work for the vast majority. Only a favored few find it spontaneous.