The biggest difference between playing a robot and hitting with another player is that a robot can hit everything the same, while a player's shots always have some variation. However, the Newgy robot is designed to give you random shots over a pre-arranged area, via the oscillator and the oscillator's range levers. You don't have to have it hit every ball to the same spot. This allows you to work on your footwork as well as your stroke.
On the back of the robot is the "robot oscillator range levers." (Editor's note: These are listed as "Oscillator Control Levers" in your robot Owner's Manual, part #'s 61 & 62.) These show the various ranges the oscillator can sweep through, depending on which setting you choose.
Assuming you've taken the time to develop decent forehand and backhand strokes, it's time to learn to move and stroke. More specifically, it's time you learned to cover a certain proportion of the table with each stroke.
Set the robot on topspin. Set the robot's oscillator's range levers to 1-4, so the robot sweeps over just the forehand side of the table. (You can adjust the robot to sweep over a smaller area when starting out, if the 1-4 setting sweeps too much area.) Put both the speed and frequency settings in the 3 to 4 range. Turn on the oscillator to about 6, and the balls will shoot out randomly to the forehand side. Return each ball with your forehand. (Editor's note: this assumes you are right handed. If left-handed, place control levers to the 3-6 settings.)
To do so, watch the robot very carefully, and move your feet to follow the direction it is pointing. Keep your weight on the balls of your feet, with your knees at least slightly bent (Editor's note: the taller you are, the more you need to bend your knees). Move with short steps, keeping your weight centered at all times. Try to be in position for each ball without having to reach—move into position so the ball goes through your forehand hitting zone.
Now set the robot's oscillator range levers to 3-6 (1-4, if you're a lefty), so the robot sweeps over the backhand side of the table. Repeat the drill with your backhand. When you feel comfortable with that, do the same drill—with the balls still sweeping over your backhand side—but use only your forehand from your backhand side.
It is important to learn to hit the forehand from the backhand side because often you will need this skill for put-away shots. You normally should not play backhands from the forehand side, however.
Next try covering larger areas of the table, but this time using both forehand and backhand. At first set the oscillator's range levers so that the robot doesn't quite cover the entire table, and practice making clean shots, both forehand and backhand, by moving to each ball, not reaching. As you improve, increase the area until you are able to cover the entire table this way.
When the robot is set to sweep over a relatively small area of the table, the frequency setting is not too important as the balls will effectively come out randomly over the assigned area either way. When you start covering the entire table, however, the frequency setting begins to matter. Start off relatively low, at a pace you can cover somewhat consistently, and work your way up to faster and faster frequencies. Consistency is the key; don't set it so fast that you are leaping and diving after balls!
As you improve, you can also increase both the robot's speed setting and how hard you hit your own shots. You should also try the above drills with the robot set on backspin, and either attack or push. Generally, attack backspin when using your forehand (unless it goes too short, in which case you should either push or flip), while either pushing, driving or looping with the backhand.
There are two basic skills the preceding drills are designed to develop. First are the footwork skills to cover the table by moving to the ball, not reaching, so that you can consistently hit clean shots. Second is what is called "neuromuscular adaptation"—the ability of the brain to quickly make a choice, and react. This is developed in the drills where you have to choose whether to use a forehand or a backhand. Developing these skills will greatly enhance your ability to play strong rallies comfortably.