On your way to the perfect press, your technique will gradually build up. You will cheat.
Any amount of pushing is considered cheating.
But knowing this may not be enough to stop doing. It is just TOO tempting.
When your toes are, despite all your efforts, still helping you, we can use the following to force ourselves to use our strength and control, and not the push from our legs:
→ Rolling toes (coming soon)
→ Shoes