1. If your cat's eyes are red, cloudy, have a discharge, she is holding the eye closed or squinting, if vision is impaired, see your vet.
You want to go to the vet to ensure there are no sight-threatening conditions.
2. If a foreign object is in the eye, gently wash the eye with large amounts of water or saline eye wash (preferred).
Whether or not you remove the object, have your cat seen by a vet, foreign objects can cause corneal ulcers or infection.
3. If your cat's eye comes out of the socket, keep the eye wet using a sterile eye wash while you head to the vet. There is usually significant head trauma associated with this in cats.