Don't use humor where it's not appropriate. Keep a joke file. Write down funny things or events so you can remember them in selling or speaking situations. There are humor tendencies. Men and women tend to make jokes about the other gender.
Religious groups are apt to take each other on.
People in bordering states tend to be on the wrong end of the joke. In North Carolina, it seems to be about farmers in West Virginia, but when I lived in Indiana, it was those farmers from Kentucky. And, of course, if you're from New York, everyone else in the world is a farmer. Risque jokes can be risky. They will get you in trouble if you say them to the wrong person.