If you, your dog or other pets have been sprayed by a skunk, combine:
1 litre of 3% hydrogen peroxide
60 mL (1/4 cup) baking soda
5 mL (1 tsp) liquid laundry or dish soap
Clean the affected areas with this solution. Avoid using the solution in pets' eyes. Rinse with water and repeat if necessary.
https://youtu.be/TI9KX932UxQ
Skunks are nocturnal animals with poor eyesight and limited climbing skills. They tend to only use their spray as a last resort when startled, cornered, or attacked. If you see a skunk, back away slowly and quietly to avoid a spray. Keep your dog on-leash when you're out walking in low light.
Learn more about co-existing with skunks.