That's a broad question, but I will try to answer it by letting you know the things you should consider when planning a career. The first step to planning a career is to do self-assessment. What do you enjoy doing? Do you enjoy problem solving? Do you like analyzing things? Do you enjoy working on teams or do you prefer to work independently (or a combination of the two)? Most career centers have self assessment tools you can utilize, so I recommend you take advantage of that to determine what your interests are. There are probably many jobs that you are capable of doing, but it is important to find a job that you enjoy as well. There is a direct correlation between enjoying a job and doing well at it.
The next thing to consider is what motivates you. Is it money? Upward mobility? Variety of work? Figure out what is important to you in a job besides the actual job duties.
The next thing to consider is how much education and training the job your interested in require. Determine if you are willing and able to make that type of commitment (if you're really passionate about a career, you can make it happen!).
Once you have considered these things, it should help you narrow down different career that would be a good fit for you. The next step is doing a bit of research. You can Google your profession of interest or your school may have access to databases such as Vault and OnceSource. Once you read job descriptions for the careers that interest you, go back to your interests and see if it's a good match for you. You can also try to do some informational interviewing with people in the profession to see what kinds of projects and activities they do in their jobs.
Bottom line, you need to consider many factors when planning a career. Also know that very few careers are linear - you will have many twists and turns in your career and that's fine. Enjoy the journey!