Do share a quality about yourself that you want the admissions officers to know about you that won't be found in other parts the applicatio.
Do put yourself in the best light possible.
Do think reflect on an experience and how you responded to it when writing your essay.
Do be sure your essay answers the prompt.
Do be yourself in your essay. This is your time to share who you are with the admissions office.
Don'ts
Don't make your essay about listing achievements.
Don't use inappropriate language in your essay.
Don't feel like you have nothing to share with the admissions committee because you haven't cured diseases, lived through a trauma or started a school in another country. You have just as much to share about who you are and what makes you ho you are.
Don't put off writing your essay until the last moment. Give this process the time it needs to be done write.
Don't forget that you are the owner of your essay. Others may help you and give you advice, but this essay is yours and it is about you.