In both singles and doubles, your ability to volley well can be the deciding factor in the match.
Most players these days can hit their groundstrokes well. If you can use your offensive shots from the baseline to work your way into the net and finish by hitting a winning volley, this could be the difference in the match.
Your idea should be to use depth to set up the point, followed by consistent, solid, and early volleys once you have reached a good position at the net. A good thought to use the placement of your volleys to win the point is to hit the ball towards the corner of the service box (the ball does not have to land in the corner-just hit it in that direction) by making contact early. For right handed players, hit forehands towards the service box on the deuce side and backhands towards the service box on the ad side (reverse this for left handed players).
The pace of the shot does not have to be faster than your normal shot since the ball will bounce once and then pull the player to the outside of, or off the court.
Using this idea to end some of the points can be the difference in your match in both singles and doubles.