Hi! That's a great question, and I think the answer is going to vary from school to school. A good first step is always to ask someone else for help. First, if you know of someone who has started a chapter at your school, go and talk to them about it! They should be able to help you figure out which steps to take to start a new chapter. Second, if you don't know of anyone who has started a new chapter, talk to the school's administration! A good place to start is always the school's receptionist or maybe business office manager, as they can help direct your question to the right person.
Best of luck!