When choosing your major, gather information and advice from many sources, especially the abundance of advisers you have available to you at Princeton. All you have to do is ask!
Your faculty adviser serves as one of your key sources of guidance and insight. Your adviser may not be in the department(s) you are considering, but all advisers are helpful sounding boards who know about a range of disciplines and the prerequisites for various departments. Take time to confer with your adviser throughout the year and not only during course registration time!
Another important source of guidance are people in the departments you are considering. For a faculty perspective, you can always turn to the departmental faculty contacts designated for pre-major advising. For a student perspective you can turn to student representatives whom the department identifies as good contacts or to peer advisers, whose names appear on each departmental page.
Your major need not determine what you do after graduating from Princeton. However, Career Services is a smart place to visit in considering your major and weighing the options available to you. The Career Services website showcases each academic department, offering a list of internships and career paths taken by Princeton students and alumni in that area of study. The following programs also have websites that should be helpful to you as you consider the connection between your major and possible career choices: Pre-law, Pre-business, Health Professions Advising Office, Program in Teacher Preparation
Other programs, such as the Pace Center, the Community Based Learning Initiative, Fellowships Advising, Study Abroad, and International Internships, may seem less obviously related to major selection, but they are also excellent resources for thinking about the larger world and how you might tailor or supplement your program of study for specific opportunities after Princeton
Finally, your residential college dean and director of studies serve as important sources of information and guidance on possible areas of concentration.