Get a high score on the GMAT -- the Graduate Management Admissions Test -- to make sure getting in is not a problem. Scores range from 200 to 800, with a score of 700 considered to be a target for getting into a good MBA program.
Business schools want people from diverse backgrounds and are not necessarily looking for any one type of student, so trying to be someone you aren't can backfire. Being truthful about your background and your experiences can be beneficial in the application process.
Ask for a recommendation, but ask for the right recommendation. A recommendation from someone who graduated from the program you're applying for may not be as useful as someone who can write about how well you work with others, your leadership skills and ethics.
Apply to schools early because competition is fierce. Top schools will accept many of the top applicants in the first round, so don't wait. Some schools see a higher number of students applying in the second round but beware that usually means more applicants and less spaces for the school to fill. Check with the school you are applying to regarding deadlines and gather entrance materials early; the entire process could take up to one year.
Write up a list of questions and practice with a friend. Be loose and don't be stuffy or overly formal. If the person asking you the question already has the MBA, this is even better.
Regardless of what school you are applying to, read the directions and follow them precisely. Not following directions will say a lot about your ability to perform in the classroom and the school most likely will not call for missing information.