Most players try to win the point by making their opponent run. Hitting the ball to the opening is a very basic, yet successful idea against most players.
Pay attention to your opponent's position-whichever side they are on in singles, try to hit the ball to the other side-keep repeating this during the point. In doubles, if the opponent just ran to the right, hit the next ball to their left-repeat for a few shots in a row.
On the other side of this idea, if you are on one side of the court in singles, recover and move towards the other side of the court as soon as you complete your follow through. Repeat this throughout the point.
In doubles, if you just moved to your right to get to the ball, recover and move to your left just after completing the follow through. Even the best players will hit 3 out of 4 balls to the opening when trying to win the point.
As the players' level gets higher, they may mix in the shot hit behind you or the shot hit right at you a little more often. Make them do this! Hit to the opening and cover the opening for more success in your point play.