I have gotten a big box and laid a blanket down in it. Should i do more ? Or what?

I would put something on the top of the blanket that can be washed … like a towel.
also be careful of the blanket because some of the babies can get under it and the mom can't find them… and they will die.
I used a sheet until after the kittens are born then changed to a blanket. (make all the edges solid/ folded… so there is no opening for the babies to crawl under.
good luck

PLEASE HAVE YOUR CAT SPAYED AS SOON AS THE KITTENS ARE WEANED.