Many players develop a small but effective set of serves, and find success with this. However, often they are limiting themselves with a lack of variety.

While it is important to develop a small set of highly effective serves that you can use over and over, it's also important to have enough variety in your serves that you can most likely find one that the opponent has trouble with.

For example, many players develop very nice forehand pendulum serves, the most popular serve in high-level table tennis. But since so many players do this serve, many opponents are good at receiving them, while having trouble with other serves. I've seen many players who have trouble with a specific serve, such as a backhand serve short to the forehand. (This has the opposite sidespin as a forehand pendulum serve, though it can be mimicked with a reverse forehand pendulum serve.) And then when I coach against this player, I find that the player I'm coaching can't do this serve! Often they can do the regular forehand pendulum serve short to the forehand, but it's the other type of sidespin that the player has trouble with.  

Another example would be fast and deep serves. Many players have difficulty with certain types of these, such as fast and dead to the middle (elbow). And yet many players can't do this simple serve, and so are giving away many points, games, and possibly a winnable match. Fast sidespins to the wide backhand give many players trouble, and yet few bother to learn these serves. And then there are the all-out forehand loopers who loop every deep serve to the backhand - and woe be the server who can't cross up this player with a fast serve down the line to the forehand!

The list goes on and on, and yet the principle is simple. Learn to serve short and long (including fast) to all parts of the table with all varieties of topspin, sidespin, and backspin (and don't forget corkscrewspin and no-spin! See article on spin if you're not sure about these two), and you'll have it all covered. While you don't need to be an expert on every serve, you should be at least proficient at most serves so you can pull out the needed ones when needed.

If you are a looper - and that means most players from the intermediate level on - then when someone pushes to you and you want to loop, you should be in one of four mental states. We're assuming you can loop both forehand and backhand, or (if no backhand loop) have very fast feet for #4.

1) Loop forehand or backhand, depending on where the push goes. This means there's essentially a line from your opponent to your playing elbow (mid-point between your forehand and backhand), and if the ball is on the forehand side of that line, you forehand loop; if on the backhand side, you backhand loop.

Advantages: You are ready to loop anything, and you don't have to go out of position.

Disadvantages: Your opponent chooses if you are going to loop forehand or backhand (and presumably will have you do your weaker shot), and you might have problems deciding which way to go on pushes to the middle, especially quick ones.

2) Favor forehand, but ready to loop backhand if it's a strong push to the backhand.This means you are ready to forehand loop most pushes, including ones to the middle and weak ones, but won't force it against a good push to the backhand, which you'll backhand loop. (Of course some might just push this ball.)

Advantages: You are ready to forehand loop - presumably your stronger side if you choose this strategy - against most pushes, both strong ones anywhere except to the backhand, and weak ones anywhere.

Disadvantages: You may have a lot of ground to cover on some shots if it's a good push toward the middle. If you are ready to forehand loop and are forced to backhand loop, may not be ready and so may backhand loop weakly or inconsistently.

3) Favor backhand, but ready to loop forehand if the push goes to the forehand side.This means you are literally setting up to backhand loop most pushes, including pushes to the middle or even slightly toward the forehand side, but are ready to rotate the shoulders to the forehand side to forehand loop if the push goes there. You are basically telling your opponent, "I'm going to backhand loop, but if you want to give me an easy forehand loop, then push to my forehand."

Advantages: Allows you to really prepare for your backhand loop, often compensating for having less power on that side. Also allows you to have less ground to cover for forehand loops. Allows you to stay in position for most loops. If your backhand loop is stronger than your forehand loop, then allows you to maximize the chances of backhand looping.

Disadvantages: You'll be doing a lot of backhand loops, often weaker than the forehand loop. Can be caught off guard with a quick push to the forehand side if you are too quick to set up for a backhand loop. Can have trouble backhand looping pushes that go to the middle if you don't learn to step into position properly for this.

4) All-out forehand looping. You basically decide in advance that if it's humanly possible, you are going to loop with your forehand. Can only do this if your footwork is fast and technically good. Off the serve, good footwork technique and anticipation can make up for not having fast feet. (Note that the logical alternative to this, all-out backhand looping from all over the table, is rarely done since there's less range on the backhand side. There are some players who do this, but they are rare.)

Advantages: You get to use your forehand loop, presumably your stronger shot. Allows you to get into forehand position so you can do a series of forehand loops in a row. Takes the indecision out of the shot since you know what you are going to do.

Disadvantages: You have a lot of ground to cover, and so can get caught out of position, both while trying to make the shot and for the next shot. May make weak or inconsistent shots if you aren't in position quickly enough.

Conclusion: Which of the above do you use?

Where should you put your putaway shots? Whether they are smashes or loop kills, there are basically three options.

Option One: The easiest spot. This usually would be the longest diagonal. This gives the most table to aim for, and so is the safest and most consistent. The down side - it's also the spot most opponents will expect you to aim for, and so is the most likely to be returned. At the beginning/intermediate level, you should aim most putaways to the safest spot since it's probably not coming back.

Option Two: Aim one way, go the other. Most often this means aiming for the longest diagonal, and then, as the opponent moves to cover that spot, going the other way, usually down the line. This is riskier as you both have less table to go for and you are setting up to go one way, then have to change at the last second, but it's also going to make it very difficult for the opponent to return this shot. It's only at the higher levels that opponents can react and cover both corners.

Option Three: The opponent's middle. This is the transition spot between forehand and backhand. At all levels this is probably the most difficult spot to react to. There are players who can almost relentlessly return shot after shot at the corners, but go at their middle and they fall apart. This is the most common spot top players aim at. The down side - it means you don't get the long diagonal to aim for, plus it's a moving target, depending on where the opponent is. Also, a forehand-oriented player may counter-attack that ball with his forehand - but if he does, he's probably moving early, and leaving his wide forehand open, which is where you would go in this case. 

Imagine coaching someone to play against you. What would you tell them? Now imagine coaching yourself to fix up the very weaknesses that you would coach an opponent to play into against you. The top authority on a player's game should be that player, so listen to yourself; you are a wise and knowledgeable coach!  

There's a myth that top players use complicated tactics to defeat opponents. Perhaps as they are about to serve they are planning out their first three or four shots? After all, chess players plan things out many moves ahead, and table tennis has been called chess at light speed.

That's not what happens in table tennis. Top tactical players don't work out complicated tactical schemes; they look at all the complexities and find simple patterns to disarm an opponent. There are just too many variables to plan too much. It's better to focus on a few simple tactics that will tend to favor what you want to do. The key is choosing those few simple tactics. That's your primary goal in the first game of a match, equal in importance to actually winning that game. Some tactics are for setting up your own strengths. For example, if you have a powerful loop against backspin, you might serve backspin so you get a lot of push returns. If the receiver pushes at wide angles, you might serve backspin low to the middle, thereby taking away some of the angle. If you have trouble with heavy backspin, you might serve no-spin, which is more difficult to push heavy. (If you fake backspin and serve it low, it'll usually get pushed.) If you have a good smash, you might serve varying sidespin and topspin serves, with varying speeds and depths. If you are quicker than an opponent, you might serve topspin so you can get right into a topspin rally.

Other tactics are to take away an opponent's strength. For example, if an opponent has a powerful forehand, a simple remedy would be to serve short to the forehand, and then attack out to the backhand, thereby taking the forehand out of the equation. If an opponent has a strong push that is difficult to attack, then serve topspin. If an opponent has strong side-top serves and a good follow-up, then focus on returning the ball deep. If an opponent has a strong forehand and backhand, perhaps go after his middle, the changeover spot between forehand and backhand. And so on.

Similarly, you can use tactics to play into an opponent's weakness or to avoid exposing your own weaknesses. See if you can come up with your own list of tactics of this type. Ideally you'll learn to play your strengths against an opponent's weaknesses. But sometimes you'll play your medium shots to the opponent's weaknesses, or your strengths to the opponent's medium shots.

Most top players focus on just a few tactics - perhaps two or three serve tactics, one or two receive tactics, and one or two rally tactics. This doesn't mean they don't use other tactics as the situation comes up, but they are standard tactics that are ingrained from years of playing and thinking about the sport. The specific tactics against a specific player are far more limited, and yet, if chosen properly, will pay off dividends.