I applied successfully this cycle and I wanted to share what I learned about the process. The first thing is timing, the cycle is a marathon not a sprint. Assuming you're a rising senior, you want to start looking at schools and the GMAT in the spring, you should be asking for letters of recommendations from professors and employers. Summer should be interning and taking the GMAT if you didn't in the spring. Fall should be when you start your actual applications and submitting them ideally in Round 1.
The first step is selecting the schools you will be applying to. You need to assess yourself honestly. It's not an easy process to do. You need to look at your GPA/Work Experience/GMAT and see where you are competitive. You need to figure out where you want to be geographically as this will influence where you will apply. If you are a splitter i.e. good GPA/bad GMAT or vice versa you will need to apply more broadly. Ideally you should apply to somewhere between 3 and 7 schools. Apply to a mix of reach, target and safety schools.
The second step is getting set for the GMAT. Depending on how much free time you have it can take anywhere from a few weeks to a few months. Buy the original guide, Jeff Sackmann, and the Manhattan GMAT Books. Beyond that I would suggest Knewton if you can afford it. You need to be consistent in studying even if it is only an hour a night. Get your baseline score and figure out how much you need to improve. For a tier 2 MSF the mean GMAT is about a 660, For a Tier 1 you should be aiming for a 700+. Schedule your exam ideally in the spring or summer that way you will have time if you need to retake.
The third step is getting your letters of recommendation. You need to get on this early as it can be difficult. Professors can be busy and it can be tough to get them to write it. Employers need to be chosen carefully, ideally you choose someone who knows you well and can write a strong letter for you.
The fourth step is putting the application together. The essays are the tough part. Applications are online starting somewhere in September usually. Take a look at the essays and start thinking about your responses. Many of the essays are similar. Most schools have a "Why Us?" and "Career" essay. Once you've written the first one the rest tend to flow from that. Print the essays out once you're done with them and read them over, that way you can more easily see any mistakes that you have made. Have a trusted friend, a professor or colleague look over your essays. Make the revisions and see if you can't get a third set of eyes to take a look at it.
Finally, it's time to submit the application. The earlier the better. Ideally submit in round 1. After the application, you may have an interview. Most good programs require one. These interviews resemble a behavioral/fit interview. Most of the time it is like this, "Why our school?" "What are your career plans?" "Tell me about your strengths/weaknesses?" "Walk me through your resume/Tell me about yourself?" "Tell me about a time you worked in a team and it failed/succeeded?". Remember to research the school beforehand and to know its strengths. Carefully go through the school's website, its viewbook and its employment data.
Hopefully after all this you have a number of competing offers and can decide on the basis of prestige, financial aid and on how the school fits with you. Choosing can be tough, but focus on how the school places and its cost.
