Never make fun of others. If you do, your listeners will never trust you not to make fun of them when their backs are turned. Do not be moody. To say of one that she is always the same is a great compliment. Sociability and friendliness are very useful and endearing traits.
Friends are indispensable, and acquaintances are always possible friends.
It is a fine thing to have a sense of humor. Indeed, it is almost always listed as a necessary element in popularity. Cultivate it, if possible. Learn what good taste is and practive it in dress, manners, and all social relations. No one is better liked as a companion than one who is self-possessed, well poised, and who knows how to behave correctly under all circumstances.