You want to become part of the employer's network. One way to become part of this network is to conduct informational interviews. Anytime you contact employers directly, be sure you have prepared and practiced what you want to say and know what you want to accomplish. By combining various job search strategies, you will likely find the greatest chance of securing employment. Networking is essential.
Many people feel uncomfortable at the thought of networking.
Yet think about how you learned about interesting classes to take or how you found your summer jobs or campus employment. You probably spoke to someone you knew, and they referred you to someone else. Don't be shy about telling everyone what you are looking for or what you need help with. They may be able to refer you to someone better able to help you. This is how your network grows.