How Do I Know If My Cat Is Done Giving Birth?

Not necessarily licking and cleaning in cats is sign of delivery of any remaining kittens. Cats always lick to be neat and clean as part of self grooming. If you have no experience of delivery in cats that it would have been better choice to get help from vet. Vets are professional and can handle any up and down during delivery of all pets including cats.

If your cat is not shaking and straining for delivery of kitten since last 2-3 hours then she has delivered all kittens. If she is straining to deliver kittens without any result then some kittens are remaining inside. If this is a condition in your cat then take her to vet immediately.

Yes more are coming when she is still breathing heavy, you know when she done when she stops breathin hard and is falling alseep just watch for another hour or so if no more babies then she is done.

It's been almost a day since you asked so it's a safe bet she's finished by now.
Cats often give birth in two stages as they have what is termed as two "horns", where the kittens from one horn are born, then a gap of up to 2 hours, then the kittens from the other horn are born.
Mother and kittens should be checked by a vet within 24 hours of birth to make sure everything is ok and that the birth process is complete.  They will give the mother cat an injection to promote contractions in the womb to ensure all placenta is delivered and the womb will reduce in size.   
Congratulations on your new babies. How many??

While she is still breathing Havel

Yes ,your cat is done giving birth.