the first thing i would suggest is a vet vist, they will give you a good idea of when to expect kittens. between 10 days to a day her milk will start comming in, but sometimes wont untill she has them. movment of the kittens will start in about the 7th week of pregnancy, and sometimes you will see a mucusy discharge when she is near to delivery, but you vet is the best person to ask.
not sure if you know , so if you do im sorry. but she can become pregnant days after delivering her kittens so it is important to keep her indoors only and away from any intacked males untill she has been safely spayed. when she is about 7 weeks into the pregnany its a good idea to start her on a good kitten food.