Know who reads your application–and help them know you.
I feel very lucky to have been accepted to, and graduated from, Stanford University. While I worked hard in high school and put my best foot forward in my applications, I want to emphasize that there will always be some serendipity in college acceptances. At the end of the day, you can only be yourself. What you do have control over--and what you can work on in your college applications--is how well you use your essays to summarize who you are to admissions officers.