Once you have produced an essay by going through the steps enumerated above, you can improve it further by going through this last section for added measure. These will help you check for final errors.
Just as a strong personal statement can get you in, a poor personal statement/essay can quickly eliminate you from the mix. When a medical school committee has a few hundred applicants, seeing typos, spelling mistakes or bad content will quickly move you to the bottom of the pile. The personal statement is a quick way to "weed out" similar applicants. With two similar applications, the personal statement can decide who gets an interview and who does not.