<p>I'm going to be applying for college this coming fall, and having scavenged through various guidebooks and online samples, I think I've found some helpful tips to write a great application essay, be it supplemental or college-specific.
Basically, the most important fact would be to focus on one topic or event in one's life and develop that so the reader feels that the writer either grew or learned something from the experience. Going deep would be a great asset in the essay, though I've noticed that many try going TOO deep and end up waxing poetic and losing touch with the reader.
Other DON'T DO'S of essay writing include NOT merely citing one's credentials. Rather, one should emphasize his or her maturity and tact through the essay's development.
Of course, this makes the essay extremely difficult to develop, especially given the 500 word constraint. Still, if inspiration strikes at the right moment, or more frequently, if you keep plugging at it, I bet everyone can make an amazing essay.
So go rock the socks off of those college admissions officers and WRITE YOUR HEART OUT, metaphorically.</p>