Directors report to board members regarding what's going on with the company as a whole. Then together, they work to develop new marketing and business strategies to help the company grow and expand.
Typically, directors have the ultimate, hands-down decision making capability, which is a lot of responsibility for one person, especially considering the type of decisions you'll be making. Any top-level decisions will come to you. You may also be responsible for approving a final budget and making sure company policies are being followed.
Some directors have long work hours, it depends on your employer and industry. Some directors will work longer than the typical 40-hour work week and many have erratic schedules that are determined by meetings, which are usually held after normal business hours.