Most funny jokes have a corny idea at their core. It’s about the delivery. Try to analyze a joke that you like and cope the train of thought as well as how it was put down.
In order for a joke to be enjoyable it has to be novel, surprising and ironic.
Novel: You can’t reuse a point made in an earlier joke.
Surprising: Save the punchline for the end, and if possible save it until the last word. Don’t double down on it by saying it again another way. Let them just laugh without your comment of “that’s what he said”, or some other unimportant space-filler. And if they didn’t laugh, carrying on won’t help.
Ironic: The soul of funnyness. A pun is ironic. A connection, another meaning of a word, or an odd application of a concept is irony. A pun in and of itself is not all that entertaining but can be used as a punchline of a well designed joke. For example, you can distract the listener from the other meaning, and build a story that implies the regular usage and suddenly turn it around at the end.
Isn’t that funny?