Cust. and Support Issue

My daughter lives with her mother as her primary residence, but we have joint custody of her. She’s with her mother 52% of the time and me 48% according to the courts paper work. She is really with me more and has been for about the last year. She has been put in a bad situation with her stepfather being violent and she is very unhappy living there at all. She has requested to be with me most of the time from now on. She is 12 years old and I have always been the one who payed child support and her mother quit work prob 4 years ago when she married. I guess i’m wondering what the next step is for me to change primary residence and would I get any support being that she doen’t work?
Thanks

You need to file a motion to modify child custody and child support based on the change in circumstances since the entry of the last order.