After grammar and spelling, the next problem that needs be checked is transition. Read your essay. Go through it from end to end, and check to see if your essay flows smoothly. Does each sentence flow smoothly to the next? Does each paragraph flow logically to the next? Each statement should be connected or somehow related to the one before it, not thrown randomly together. Next, limit the use of "I" in the beginning of most sentences as it is already obvious that the essay is a piece written by an individual.
The first place that you should look for sample personal statements is on the website of the school in which you are attempting to get into. If you can find samples of the admission essays of others who have already been accepted into the school then you can really begin to dig deep and find out what will be expected of you. Depending on the school in which you are trying to gain entry to, finding these samples can be easy or darn near impossible. When the latter happens you can always turn to the internet for help. Just as with anything else these days, the internet has an unbelievable amount of websites with samples of various types of admission essays. You can begin by conducting a Google, Yahoo, or Bing search on 'personal statement examples' and then begin to look at the different results that come up.