How do you breed hamsters?

You put a boy hamster and a girl hamster together, and as long as they’re mature and nothing’s wrong with the plumbing, you should end up with baby hamsters. Sometimes you even buy a female that’s already pregnant and surprise, surprise, you find some little hairless babies in the cage one day.

You will probably need to separate the male from the pregnant female, however. (If I remember when I used to have hamsters.)

There may be a place online where you could research hamster genetics, if you want to take it that far.