Dress well (think pretty and classy, in the California style) and be kind, considerate, friendly, and animated. See if you can use the usual types of questions (major/hometown/summer activities) to open up about yourself so that your rusher can get to know you as a person. If you find a mutual connection, go with the flow of the conversation.
Don't stress too much about it, though. Recruitment is lots of fun. Enjoy your parties!