To make a flea-repellent oil follow these directions. Do not use this on cats only dogs.
Take 20 ml of extra virgin olive oil.
To this add
7-8 drops of Peppermint
1-2 drops of Citronella
3-4 drops of Lemon
3-4 drops of Clary Sage
Mix this together and add a few drops to a collar , bandana or rub on the dog. This will help repel fleas but does not kill them. Do not use on cats!