DO NOT visit Sunnydale. Sunnydale is the hellmouth, the centre of all mystical convergence, which means that there are demons, vampires and other kinds of evil.
DO NOT ever go into the teaching profession, and be a teacher that works in Sunnydale or Sunnydale high school. (Let's not forget what happened to Principal Flutie and Doctor Gregory).
DO wear a cross to ward off the vampires. One look at that cross and they will shriek away in fear.
DO have a stake tucked away in you shirt or your bag.
DO have some sort of cage ready in case you want to trap something in it.
DO NOT go to school at Sunnydale high, the place itself is a hellmouth and the centre of mystical convergence.
DO go to the library at Sunnydale high, Giles has a book to fight off every kind of evil.
DO NOT ever invite strangers into your home, and if you do be alert!
DO have a square jaw. Living or visiting the hellmouth, you would expect to get hit a lot. Of course if you had a square jaw, you will never have any bruises of any kind which might have indicated that you were hit by someone or something.