How do you take care newborn baby hamster?

If the father is still in the cage he should be separated. Male adult hamsters have been known to seriously injure young hamsters. The mother will do all the work taking care of the baby. Just make sure she has a constant supply of fresh water, dry bedding, and fresh food. You may also put a couple small strips of flannel or soft cotton fabric in the cage for her to line the nesting area with. Don't put it directly in with the babies. She will put it where she wants it herself. Other than that just keep the cage in a quiet area and let her do her thing. When the baby gets a little bigger, you will be able to care for it just like you do the adults.