Most importantly, find someone to coach you. However that someone cannot be just anyone. Find someone who is good and has a good track record. Most students underestimate the importance of good essays and interview preparation. Schools receive thousands of applications a year. A well-formulated application distinguishes itself from the hastily put together ones; it is obviously worth the effort so work hard on your application and seek reliable guidance.
Secondly, don’t be scared to apply to highly ranked schools simply because you don’t have a GPA of 4.0. You would be surprised at what a coherently articulated story with good essays, and a convincing interview can lead to.
Finally, prepare for your GMAT early and apply at the earliest to increase your chances. This obviously does not guarantee a spot in your dream school; however, it is your job to give yourself the best possible shot. Applying last minute won’t help. We have all heard it… The early bird catches the worm… don’t hesitate, because if you do, you will lose…