Good question.
Start with the schools that are A) not your top choice(s), and B) have a normal set of essays. By normal, I mean schools that ask standard questions like "What career do you want to do and why" or "describe a failure and what you learned from it".
After you finish said essays, save them, and work on other schools. Once you feel your story is airtight, go back and revise anything you've done prior.
Good luck!
Start with the schools that are A) not your top choice(s), and B) have a normal set of essays. By normal, I mean schools that ask standard questions like "What career do you want to do and why" or "describe a failure and what you learned from it".
After you finish said essays, save them, and work on other schools. Once you feel your story is airtight, go back and revise anything you've done prior.
Good luck!