You need to go to Middle School, High School, College and if you want to extend your career, University. You must be an A student. No bad behavior and a high GPA throughout high school and college. You have to be well educated and with good manners when you work with other people.You can prepare by finishing high school with a good GPA and grades. Take AP classes during high school.Take electives like: anatomy, physiology, criminology and computer applications.