3. Be prepared to walk a lot.
People forget just how big Disney parks can be, and Magic Kingdom is no exception. On any given visit, you will likely walk at least five miles throughout the day, with some people reporting numbers in the double-digits. This might be considered a good or bad thing depending on your outlook, but in our experience, a lot of people come unprepared for this and end up with sore feet, cranky kids, etc.
Our recommendation? Wear comfortable athletic shoes and plan to take breaks often.