An alarming number of applicants get disqualified on this first step. Set aside a substantial amount of time to only fill out the application. Fill in all fields and briefly explain the reason if you can't for a specific field. Photocopy the application and prepare several drafts -- chances are that mistakes will initially be made but these should never appear in the final application. Show a draft to a colleague for clarity and points to revise.
A person's resume may have taken up different forms as he progressed through years of work experience. Highlighting applicable experience from these different resumes is standard, but many MBA applications require a specific format and presentation that may have significant differences from a standard resume. Follow these instructions precisely, utilize clean, academic wording and explain each experience thoroughly yet concisely.
An MBA applicant with at least five years worth of experience will have numerous potential references. However, the trick is choosing the right one and that person writing the right content. Contact previous managers or professors who were directly involved with your strongest experience and helped develop your strongest skills. As you request a letter of recommendation, ask them to emphasize these elements and how this set you apart from all their other students or employees.
Admissions officers read through a lot of essays -- catching their eye and embedding yourself in their memory is tantamount to getting to the next step. Write in a personal yet professional tone to keep the voice yours and yours alone. Highlight non-standard experiences and how you would be a unique addition to their program. Use active voice and show your various achievements in the past years. The goal is for the admission officer to immediately say "yes". Structure your essay not to conform to "standard essays" but to stand out.