Homemade Tick Repellent
Put in spray bottle:
1 c water
2 c distilled white vinegar
2 tb vegetable or almond oil, or lemon juice, citrus oil or peppermint oil
Spray onto dog's dry coat, avoiding eyes, nose, mouth and genitals.
For outdoor pets, spray this on two or three times a day.
Rose geranium oil is another tick repellent; put two or three drops on your dog's collar.
It seems that nothing does the job 100%, but these measures do make some difference and are at least worth trying.