How do you become an international school teacher?

How does one become a teacher at an international school. Any documentation for this? I don't know what kind of certifications or degree is required. What experience, background, what is the timeline of the process. Scholarships? Grants? What if you are from third world country? Do you get supplied with a living space or you get money to cover for rent? How does it work? I know this is a very common question, but it would be very nice to have a comprehensive guide to this issue.