We hope that you use your time in China well and come back thoroughly immersed in language and culture. You will definitely have some culture shock on your return and find yourself missing certain foods or drinks, or even sights and sounds. Your suitcases will likely be full of souvenirs and all kinds of things, but please spend a minute thinking about what kinds of research materials you could bring back with you.
Will you be taking advanced language classes? Want to write a senior thesis? Would you like to do an independent study? If so, consult with the instructor you would like to work with and bring the materials back that you think you will need. Many students want to work on popular culture - television shows, advertisements, comics, popular magazines - and these are exactly the kinds of materials that libraries have a hard time supplying. So collect them while you can and send them home by sea mail so that they will be waiting for you when you get back.