For those of us that have not been offered a position at or ownership of our father's business, it is extremely necessary to network. It creates references, opportunities for employment, and resources in our specific fields.
Commonly students hear "you have to network in college" or "it is easier to network while you are there than it is later". What most students do not hear is how to do this. Now in my senior year, I wish someone would have told me how to do this, but also to start doing so in my first year. I am just learning to do this now (5 weeks before graduation) but I think what makes students apprehensive about networking is that they are not confident in themselves and their possible value to a professional career. This happened in my case and I do not know what profession I am interested in, thus it is difficult to create a business card or market myself. It is, however, fairly simple to talk to your professors, fellow students, and class guest speakers, as you are required to spend time with them on a weekly basis.
The Hope College Office of Career Services has created a pdf that is helpful (our Career Center has similar services). I have attached it here: http://www.hope.edu/student/career/resources/Networking.pdf