I am scheduled to take the GMAT tomorrow afternoon, however, I am not ready and have not been getting practice tests scores close to what my goal (690+). Would it be better to reschedule and and sit for the test another time when I am able to consistently score in my target range on practice tests or should I sit tomorrow and see what happens? I am concerned that if I completely blow it (score in low 600s), it will look bad on my apps. Thanks in advance.