How can I best convey my attributes to stand out from all of the other applicants?

You should talk about the achievements you are most proud of and demonstrate how these helped form who you are today. This will not only give the admissions office an idea of what you have done but also what type of person you are. There should also be some kind of evaluation regarding your achievements, either stating something that may not have gone the way you expected and how you overcame this or something you learned about yourself or the enviroment you were in which you had not expected or is controversial. This can strengthen your application as it demonstrates your critical thinking.