15. Learn the professional rules. On your first day, your employer will have a description of your responsibilities — either written or verbal. This is what you should do to be successful at your job. "With that being said, there is usually a gap between what you should do, and what actually happens," Parnell says. "This is important because while you shouldn't neglect any articulated duties, there may be more that are implicitly expected of you. It is usually best to find this out sooner rather than later.