How can you tell if a cat is just about to have kittens?

First of her waters will break and you will know this as she will leave a trail of drips behind,plus she will have a soggy behind other clues are her nipples will turn a darker shade of pink,and she will begin to nest build looking in to cupboards ect,and another thing is when labour begins she will appear restless and start pacing around the room meowing,and if you look at her tummy at this time you will be able to see it moving.