How do you know if your ready to move out.?

Im really fed up with my parents and I want to move out really bad but at the same time I wonder if im wrong by wanting to move out. Im 19 years old and im a good kid. I go to college and i work at the same time. I give my mom half my paycheck every time I get it and just today i dropped my sisters ipod on carpet from my bed and it didnt break or anything and she said i had to give her half my paycheck and to help her pay for half of her expensive itouch. I try to help pay for the home expenses too and i understand i need to if i live there but i think she abuses that. She will also take my money away because I supposably give her mean looks. She also yells at me everyday over the dumbest things because she is so controlling. I have to call her every where I go when she knows where im going. I have to call her when i get there and when I leave, Im a good kid I dnt go out the only places i go to are work school or out to dinner and movies with my bf. If im at work and i dnt txt her during my shift she will call my workplace and start yelling at me on the phone. I help them so much. They dont know much english so im the one that calls everywhere, writes letters to companies, interprets everywhere and so on. I dnt mind doing all that but I really wish they would understand me. If I ever try talking to her she will say im wrong and go in denial and say shes right and im wrong o matter how wrong she really is. I really want to move out but at the same time im scared. Im scared of what she will do. I know im old enough to move out but she will never understand that because she is so controlling,How do you know if your ready to move out.?
Just do it. You are not a baby anymore. You are 19 and you seem like a smart girl.