Here is what I would do...
1. Be certain that you really want USAFA, even if next year. If you accept, there is an expectation that you will work to excel, and reapply. You have "a second bite at the apple" and must take the opportunity very seriously.
2. Personally contact each of the Prep Schools to discuss and fully understand their programs, costs, expectations, deadlines, etc. All are very good but they vary.
Disclosure: My DS attended NWP last fall and I enthusiastically endorse the Durbeck's and their program.
3. Choose the program that fits best for you. Understand the historical success of that school with Falcons and Appointments.
4. Accept/decline the scholarship offer. Truth is, after not being appointed this year, you may have second thoughts or prefer a Plan B school.
5. Personally notify your ALO and Congressional contact that you received the Falcon and plan to accept. You will need a nomination again next year so plant those seeds early.
6. Be humble and committed. There are many here who won't get the opportunity you received. You will be a year older and may be better prepared for USAFA than a direct appointee.
7. Hand write thank you notes to all involved.
8. Get in shape and be ready to work.