For every action there is an equal and opposite reaction.
Knowing this, you can assess each action that you make in the water. Observe the reaction.
If you sweep your hand to the side, where do you think your body will go?
To the opposite side!
Are you trying to move to the side of the pool? I doubt it.
If you want to get across the pool, push the water behind you.
Experiment next time you go to the water.