Judgment is necessary as well. Go against the textbook occasionally. The leader stands out, so the person who stands out appears to be the leader. CEOs are humorous. They have and use a sense of humor.
Secure people can laugh at themselves.
The typical child laughs 400 times a day. Adults laugh about 15. You can have a serious nature as well as a sense of humor. Don't take it to the extreme. Be willing to try it.