As mentioned, this part of your application can be used to decide whether a school wants to invite you for an interview or not. Schools only accept students who have been invited for interviews, so getting to this step is a huge part of the process.
Check for grammar, punctuation and spelling. If you're not confident about these aspects then ask someone you can trust or hire a professional to check the personal statement. _ Review your statement and ask these questions: _ Have I answered the questions required? _ Have I put forward the best examples of experiences and effects that are relevant to my field of study or who I am? _ Have I effectively answered the main question here _ Why should the Graduate School accept me over my fellow applicant? _ Does this statement reflect who I really am or do I sound like a "too good to be true" parrot? _ Would I fall asleep if I had to read this or would it grab my attention? _ Have I let my sense of humor get carried away? Do I sound too opinionated or extreme in my views? _ Have I addressed any weaknesses I have e.g. low GPA or LSAT?