This post is designed to offe the starting points of selecting, talking with, and managing the work your recommendation writer will contribute to your MBA application.
1. Choose the Right Person
There are three basic principles to keep in mind:
a) Choose someone who knows you well, rather than someone with an impressive title.
It isn't worth it to try and impress your reader by getting a referee who has CEO in his/her title. First of all, the CEO of your company is probably not famous anyways. Moreover, if you do play the "impressive referee game", you're likely to be competing with people offering reference letter from current or former Presidents, so you'll end up using the game. Finally and most importantly, if your referee with the impressive title doesn't know you well because you two haven't worked closely on anything, it'll be immediately obvious from the contents of the letter, and your application reader will be less willing to value it highly - because their job is to learn something about you, and the weak or vague reference letter won't allow them to do that.
It's always best to find someone who knows you well, and has been in a position to observe your work, and assess the skill set you have gained from your work.
b) Choose someone who has been in a position to judge your performance recently.
Avoid the direct supervisor who you worked with from 1996 to 1998. The obvious reason is that no matter what they have to say about you, it'l be extremely difficult for your application reader to feel like they understand who you are, what you are good at, and how you work with or lead others now. Always aim for more recent supervisors wherever possible.
Moreover, avoid choosing a colleague, or subordinate. It is best to use someone who was responsible for or responsible for evaluating, your work. Choosing a colleague may compromise the effectiveness of the letter, especially if the relationship is vague or hard to understand.
c) Choose someone who can go beyond the shallow compliment level.
The letter needs detail on what you have done, and an analysis as to what this says about your strengths or areas in need of development. For this, it is best to find a referee who can describe one of your accomplishments or projects in detail, and with specific examples of what you did, as well as their own clear reflections as to the impact you made, and what the experience says about who you are and what you are good at. There is nothing less effective than a recommendation letter that is full of nice adjectives (friendly, smart, great, really great) but short on detail.
2. Buy them Lunch
It is important that you sit down with your referee and have a conversation about your story. By this I mean why you need an MBA, and your future goals. Doing so will allow you both to discuss any relevant skills you feel you have towards this goal, and possible examples of how you have shown them at the place of work shared by you and the referee.
Note that this is not you lecturing your referee about what to write - instead for the two of you it is an opportunity to brainstorm and reflect upon your experience, to consider examples which may help to show you in a clear way. Ultimately, it is up to your recommender to choose what to write about. But by discussing the topics listed above, you can help them to understand where the MBA fits between your background and future, as well as what you aim to gain from, and possibly contribute to, the program.
3. Manage the Schedule
This is not to be overlooked. Your referee - often your supervisor or someone superior to you in some way - is very likely to have a busier schedule than you do, full of commitments to keep with many people. While there is no doubt your reference letter will be impotent to them, there is also the risk that it won't get done in a timely fashion, or will at least be pitied behind other commitments, and this can cause you undue stress at a time when you should be focusing your energy on your own essays and applications.
One strategy I have seen work well is to set and then stick to early deadlines.
The longer they wait, and the closer they get to the actual application deadline, the greater the chance your letter will be put together hastily, and therefore ineffectively.
If the drop-dead date they need to submit their letter is January 5th, try and get them initially to finish their letter by December 1st. This way, if they miss that deadline, there is an opportunity for you to extend it 1-2 weeks, and ask them to ensure they not miss the second deadline. Even if they miss that, a final reminder can usually be effective enough to get them on the case before the holiday season begins.
Earlier is of course better - so encourage your referee to start in on the letter shortly after your face-to-face meeting: this way you can help to ensure that what was discussed is fresh in their minds.
There's a lot to manage when it comes to applying to an MBA program. Don't forget to manage the recommendation letter process as well.