How do I take care of a baby blue jay?

My little sister found a little bird in the yard and then my cat comes along and snatches it. I rescued it and now it sits in my living room in a box. It is hungry but i have no clue what to feed it. one website says find some blue jay food and make it soft. and another says like berries.. my ma says worms.. so far i have cut up worms and blue berries and fed it.. i don't think it is the healthiest thing in the world for it but its got to be good for now right? but does anyone have any tips for me and what to feed it.. i don't want to watch it die but i have no way to get it to a nature center