Understand what it means to be a director of a company: You should understand that your role will instantly turn you into a public figure different from what it was when you were an employee. Some of your personal information may not be private anymore.
Learn about governance : You must start learning about governance. You can find lots of courses on this. Learn from those who have been on the boards of companies for many years.
Develop and promote your brand: You can do this by ensuring you use your unique skills and experience to solve problems even outside your personal area of specialty as an employee.
Understand how your company works: You should understand important information about how your company operates.