1. Know what you want
Many people apply to business school because they are dissatisfied with their current jobs and are looking for a change, but they're not quite sure what they want. An MBA can indeed open doors to new industries and roles, but you need to research and plan your post-MBA goals thoroughly before you even apply. Think you'll have the time and the energy to ponder a gazillion career alternatives once you get to business school? Wrong! The on-campus recruiting process ramps up very quickly during the first year, and you will be expected to pick a niche very early in the program. On top of that, the first year is designed like a boot camp in order to test your limits, and doing the mental equivalent of midnight push-ups in the rain doesn't leave a lot of room for soul-searching and navel-gazing. Finally - and most importantly - business schools won't even admit you unless you can persuade them in the application stage that an MBA makes sense given what you've done in the past, what you hope to do in the future, and how the two connect. You need to write a business plan for your career before you even think about applying for an MBA.
2. Whip your current job into shape
Business schools and corporate recruiters will scrutinize your pre-MBA history. They want to see increased responsibility and recognition over time. They want to see initiative. They want to see impact. They want to see big-picture thinking and a sharp analytical mind. They want to see both hard and soft skills. They want to see someone who can make good decisions with imperfect information. They want to see someone who can lead but also follow. They want to see someone who can motivate a team and make it better. If your track record doesn't demonstrate those things, give yourself time to whip your current job into shape before applying to business school, and if your current job won't let you make an impact, it's time to move on to a job that will.
If you can't change jobs right now, or you're applying right out of college, make sure that your extracurricular life demonstrates those accomplishments and skills. One of the biggest misconceptions among applicants is that they can go to business school in order to build a track record. The reality is that you won't even get in the front door at a good program without one.
3. Women, assert yourselves
After working with many MBA applicants, I've observed a pattern: women are often more reluctant to show off their achievements than men are. As a woman, you should overcome the habit if you want to succeed in business school and beyond, as both business school and the business world will require you to toot your own horn over and over again. I work closely with female applicants on this reluctance so that they become much more comfortable articulating and defending what they bring to the table. It's a life skill you need to master.
4. Acquire international experience
The business world - and business schools - greatly value international experience and language skills. At the top business schools, it is quite common for people to be completely fluent in two, sometimes three languages. Especially if you are single and childless, take advantage of that freedom now to acquire international experience. It's harder (though not impossible) to make that happen when you have a spouse with his or her own career and school-age children.
5. Build your communication skills
The business world complains bitterly that even star students emerging from top business schools cannot communicate effectively. Many graduates are missing what employers consider the most basic communication skills, and while business schools have begun ramping up their training to address that complaint, honing those skills is an easy way to stand out from the crowd. It's never too soon to work on your spoken and written English and learn how to communicate your ideas succinctly, professionally, and effectively.