Firstly, begin by preparing the potatoes. If you choose to leave the skin on, make sure you wash and scrub the potatoes thoroughly with a kitchen brush, in order to get rid of any dirt. If you do not want the skin, proceed to peel the potatoes and wash them thoroughly.
Once the potatoes are clean, slice them into French fries and place them in a large bowl filled with cold water. This will keep them fresh, and prevent them from browning as you work on the coating.
After the potatoes are sliced, and are soaking in the water, place a large, heavy skillet on the stove over medium heat, and pour in the oil. While that is heating up, begin working on the coating for the French fries.
In a large bowl, sift the flour, garlic salt, onion salt, (regular) salt, and paprika together, and mix them until they are fully combined. Then, pour in enough water to make the mixture into a loose sort of paste, thin enough to be drizzled easily from a spoon.
Once the oil is nice and hot, start dipping individual French fries into the batter and dropping them into the oil one at a time. Do not coat and drop in multiple fries, and when dropping them in, make sure the fries do not touch each other, as this will cause them to clump together and become soggy.
Fry them until they turn golden brown and become crispy. Then, remove them from the oil, drain them on paper towels to get rid of excess oil, and serve.