Don't worry if it's time to accept your top choice college's offer of admission and you don't know what you want to study. Many students begin college with little or no idea what they will eventually choose as a major. You don't have to declare a major right away, so consider the following points to make sure you go into the right field of study.
Pick a college or university that has areas of study that interest you. If you are interested in humanities or the arts (if you could see yourself as a historian or English teacher, for example), you'll probably do well attending a liberal arts school. If computers, architecture, agriculture, or engineering have always intrigued you, consider technology-driven schools. Some of the larger schools offer both. (You can gain some insight into a particular university's programs by looking at the types of degrees they offer: Upon graduating, would you receive a Bachelor of Arts degree, a Bachelor of Science degree, or do you have the option to obtain either?)
Understand that although you don't have to declare a major as a freshman, some universities that are composed of separate "colleges" might require you to choose a college. For example, once agreeing to attend a university, even if you haven't selected your major, the school might ask you to declare your entrance into the College of Arts & Sciences, the School of Education, the School of Business, or the College of Nursing. If you picture yourself working in the business world, or as a teacher or nurse, you should enter the appropriate school at the university. If you're interested in the sciences, arts, or humanities, enter the College of Arts & Sciences. If you have absolutely no idea where to start, you should enter the College of Arts & Sciences because it usually offers the most majors and most varied courses from which to find your niche.
Declaring entrance to a particular college is not a permanent decision. Say you entered the College of Nursing only to discover that you faint at the mere thought of vaccinating someone; you can still change your mind and transfer to another college at the end of a semester or school year. You might set yourself back a semester or be forced to double up on classes to catch up, but that's better than finishing a degree program that doesn't appeal to you.
If you think you might want to major in something but aren't sure, take one class to see what it's like. Most degree programs have classes that all students must take to obtain a major (for example, a student who wishes to major in Journalism might be required to take a class called The History of Media before any other.) Take the introductory course and see how you like it and then decide whether to continue with the program.
If you still have no idea, remember that many colleges (larger schools, especially) offer a general studies program to freshman (and sometimes sophomores). These programs usually allow you to explore various options and remain undeclared for two to four semesters before you have to choose a major. Usually, these programs also assign you an academic advisor who helps you figure out what you like and what you don't and guides you toward the major that suits you.
Remember, you're not the only one who doesn't know what career direction to take. A lot of college freshman haven't selected a major. Still more students who have selected a major will change it at least once before graduating. Your freshman year is largely a time for exploring your options, acclimating to campus life, and taking the required courses that all students need to graduate.