It's best if you can flush under the eyelid with normal saline. Saline flush can be bought at the pharmacy, or supermarket in the eye care section. You can make saline at home with salt and water if you don't have any, or you can't buy any. Below is a link to a saline recipe:
https://intermountainhealthcare.org/ext/Dcmnt?ncid=520684503Flush the eye for one minute and gently wipe away the discharge with a warm/moist cotton or cloth. This can be repeated daily as needed. Below is a link to a good video that demonstrates how to flush the eye.
https://www.youtube.com/watch?v=_lXVNMcPzhsThe vinegar bath may help to remove some fleas, but is not expected to rid her of the infestation. It can also be very damaging to the skin and make things worse. There are better options for treating fleas and a local vet would be the best person to ask.
Treating for fleas is not just restricted to the host, because fleas can reproduce and nest in the environment and continually cause an issue. Below is a link to a short article that explains the best way to treat your dog and environment for fleas:
https://www.petcoach.co/article/5-tips-to-get-rid-of-fleas/I hope that helps and all is well with Sky.