A great exercise to conduct before you begin to put together your admission essay is to start with a sample. This way you can see exactly what goes on a personal statement and you can also check out how the tone of the writer is and what they actually are emphasizing.
When you allow a fresh set of eyes on your admission essay it is almost as if your personal statement is getting practice. After all, your statement will ultimately end up being read by one or more people while your application is being reviewed so it makes sense that a well read personal statement should do better in its final stages. Why have the reviewers catch the mistakes that someone else can catch beforehand? It is far better to catch a small mistake that can cost you admission, before it actually has the chance to cost you.