As a student ( international at that) I had enough concerns and queries keeping me up all night.
A friend recommended a book - Donald Ascher's, Graduate Admission Essays.
This book encompasses every bit of information a student applying to graduate, professional or doctoral programs require.
It furnishes details on what to study and why. By making us question our interests , it helps abate confusion.
A detailed section on financing you education and several links to scholarships have been provided.
Formats and samples of LORs and SOPs make the bulk of the book. You can gain information on how to write your personal statement and make it unique, insightful and power packed! Just make it a point to write down the answers to every question he asks. Also, dont skip chapters .Make notes and go through the book once thoroughly before proceeding for a detailed second read.
Inputs about graduate level examinations amd University selection are also provided in the book.
P.S: This book is definitely worth the investment. I applied to 7 MPH programs and was accepted by all of them. Infact 4 of them were in the top 10 ( including Hopkins at 1). I'm sure there are people who accomplished better without this book, but for those in need of some extra boost, do check out the link above!