1. Contact the school as soon as possible: You can write a polite email or letter to express your decision to the school, stating that you don't want to apply for admission to the school. You should thank the school for admitting you and honestly explain your reasons. Please make sure that your expression is clear and respectful, and avoid offending or hurting each other's feelings.
2. Reconsider your choice: If you are uneasy or uncertain about not going to this school, you can consider discussing your ideas and choices with your parents, teachers or consultants. They may provide some useful suggestions and support.
3. Explore other school choices: If you have other schools you want to apply for, you can contact them as soon as possible to ensure that you still have a chance to apply and be admitted to other more suitable schools.