You don't have to go to a lot of trouble to achieve this. You need a plan. Example, where will you live? How will you make enough money to pay room and board, bus tickets, phone, clothes, shoes, hygiene products, entertainment, and food? Tell your parents that everyone needs a break and you would like to try it on your own for a bit, but come for visits.
You have to petition the courts and have a VERY good reason to do so. Its not easy. You cant get emancipated just because your parents dont let you do what you want and you dont get along. You have to satisfy a judge and probably a case worker that its necessary.