Graduate Chapters

This is my senior year and the sorority that I want to pledge is deciding once again that arent going to have a line. This decision that they are making was once made before and thats why I never pledged. Being as though this is my last year in undergrad I wanted to know how can I go about pledging grad chapter. The graduate school that I will be attending is in NY and its a white school so they dont have any BGO on their campus. Can someone give me any advice about how to join a sorority in graduate school.