Make It Personal!
When I lecture about writing personal statements, I perform the following experiment: I ask my audience four or five general, superficial questions about their backgrounds and goals and ask for a show of hands. For example, "How many of you feel your courses have prepared you to succeed in graduate or professional school?" "How many of you have had work or volunteer experience that is relevant to your career goals?" OK, you have the idea. Usually, all or the overwhelming majority of the hands go up. Then I ask, "Why did I ask these questions?" Someone will usually say, "Because we're all the same."
But of course my audience is not "all the same." And you are not the same as those you are competing against--unless you write on a very general and superficial level. If you write on the same level that I asked my questions, you will fail to distinguish yourself from your competition.
You need to use your unique experiences and specific details from those experiences to bring you and your essay to life. Don't write about volunteering for the homeless; write about Joe, the homeless, Vietnam vet with the toothless smile who taught you something specific that you will carry with you. Don't write about your trip to Europe; write about watching a Gypsy troupe perform a Rachmaninoff concerto that you had played many times, but never understood before sitting under that grimy circus tent in the Ukraine. Many students can write about volunteering for the homeless or traveling in Europe, but only you can write about your memorable experiences and their impact upon you. Those unique anecdotes will be how admissions officers remember you and your essay.
In addition to distinguishing you from your competition, experiences and anecdotes are much more interesting to read than generalities and platitudes. Think about the lecturers who just give the theory and principles and compare them to those who bring the theory alive with real examples and anecdotes. I'll take the latter any day.
Do you want to write a memorable essay that is truly revealing of your unique experiences and personality? Use specifics. They will bring your essay to life.