it does not have to be exact, but just know you will add the flour three times. the milk will be divided into half, again it does not have to be precise but just know you will add the milk two times.
to the wet ingredients (egg mixture) you will add one third of the flour, folding it in with a spatula. then you will add one half of the milk, folding again with a spatula. repeat and then add in your last third of flour.
folding means that instead of stirring you will lift the ingredients up from the bottom and fold it on top until it’s combined evenly this helps 