Pictures are useful...
What do you have on hand? I'd bring her inside and try to rinse the eye with an eye wash if you have one or just sterile saline solution (you can boil salt water if you need). She'll need to be kept separate in a quiet, clean place while her eye (hopefully) heals. Besides supportive care, keeping the eye clean and making sure she eats and drinks, I don't think there is much you can do. Hope she's okay...