Hi, basically I am 20 and I have 2 younger sisters 15 & 8. We all live together with our mother who has been for a long time mentally unstable and recently she has gotten to the point she is Extreamly unfit to look after us at all. I want to take custody of my younger sisters but I do not know what to do or how to do anything referring to taking custody also we do not have that much money at all so we can't afford too much. I need help; we all do.
So if anyone could help giving advice on what to do would be muchly appreciated.

If you are all living with your mother, there is no way for you to get custody. You would have to have a place of your own and be able to prove you can support yourself and your siblings.

If you feel mom has deteriorated to the point where she is unfit then call family services and report it. Tell them you are willing to care for your siblings, but that you need help.