Today there is a lot of controversy surrounding whether you should be hitting up or down on your driver. Personally, I don’t like either of those options as a concept in your mind.
When people are making conscious moves to hit up on their drivers, they lift their body through impact, creating a heel hit. Conversely, people trying to hit down on the ball tend to come too much from the outside and hit the ball with the toe of the club.
I like to simply use the equipment; this is why you buy these expensive drivers. Swing more on the plane of the ground — around and level — which allows you to hit the ball more solidly with the loft of the club doing the work to get the ball into the air.