Start with finances, since they have the potential to eliminate a lot of schools. How much can your parents realistically expect to pay? If the answer is “I don’t know” then that’s your first job: have the discussion with your parents tonight-- after dinner, when the dishes are done and things are settled for the night.
Next: geography. What part of the country are you looking at?
Major?
School size-- do you have any idea of what you prefer?