A common problem when facing a weaker player is literally go into the match with the tactical plan of not playing your best. Rather than play your normal attacking shots, you play soft, hoping not to risk the more difficult shots that make you the better player. It's often a mistake. 

This doesn't mean you should be ripping shots left and right against a player where you could win without taking such risks. But if you are used to mostly attacking at a certain range of speeds off a given shot, and hold back on this to play "safe," you're more likely to both miss the shot while giving the opponent an easier shot to respond to. Holding back usually means you take conscious control of a shot to soften the shot for "safety," which means you are throwing away much of the muscle memory you've trained so hard to develop. Result? You play soft and erratic, and the opponent has shots to tee off against while not facing your best shots, the very ones that made you the better player. That is risky play. 

So it's usually best to just play your game against a weaker player, focusing on the type of tactics that will allow you to play your best game without playing overly safe or risky. By doing so from the start, you spread the "risk" over the entire match, and guess what? While individually some of these aggressive shots might be "risky," the risk goes away if spread out over an entire match. If you would normally loop a given ball rather hard, then do so, and let the muscle memory guide you. 

At the lower levels, pushing is often over-used, but at the higher levels, many underestimate their value. All top players have excellent pushes. However, advanced players - and even intermediate players - rarely push against deep backspin to the forehand, unless they are choppers. (And even choppers will often attack them.) It's simply better for them to attack, usually with a loop. (The same can be said on the backhand, if you have a good backhand loop.) So … should you develop your forehand push?

The answer is yes - but not necessarily against long backspin to the forehand. You need to develop your forehand push mostly against short backspin to the forehand. Against this ball, you can attack, but pushing is often the better bet. You can push short, push quick and long, go for angles, heavy spin, etc. - all sorts of variations. And because you are closer to your opponent, he has less time to react. (At the same time, don't predictably push - learn to flip short balls as well.)

The problem is how do you practice your forehand push? If you push forehand to forehand with a partner, then unless both of you are practicing short pushes, you'll be practicing pushing against long balls. The answer is to develop the forehand push this way with a partner, but once it becomes relatively advanced, start focusing on drills where you start the drill by pushing against a short backspin, and then continue the drill/rally with other shots. You won't get as much repetitive practice this way, but you'll practice what you need to develop. For example, your partner serves short to your forehand; you push quick off the bounce to your partner's backhand; he pushes quick to your backhand; and you loop, either forehand or backhand. (Or, alternately, your partner loops off your forehand push, if it's "his" drill - and you still get practice pushing!)

Meanwhile, a nice drill is to push forehand to forehand (or backhand to backhand) where both players push short - but the first time a player pushes long (by mistake), you loop. This develops your short push, develops your loop, and best of all, it develops your judgment on whether a ball is long or short.

Some players have difficulty with serves that go short to their forehand – it's awkward for them to reach over the table for those serves. However, there's a tradeoff – you get an angle into the server's wide forehand. This means that 1) you have more table (its 10.3 feet corner to corner crosscourt, vs. 9 feet down the line), 2) your opponent has more ground to cover on that wide forehand, and 3) you can move your opponent out of position by going to his wide forehand.

However, there's another option – fake crosscourt, but put the ball down the line. Often you don't even need to do this aggressively – just push or gently flip it down the line. What happens is that your opponent, knowing he has the wide forehand angle to cover, and also knowing that most players don't take the ball down the line as often, moves to cover that wide forehand angle. This leaves him open down the line – which is what you do. Surprisingly, if you flip, it's sometimes better to do this shot softly, so your opponent can't use your own speed to rebound your ball back, making up for his being out of position and unable to make a strong shot on his own. A soft down-the-line flip will often completely disarm the server. (If you push, a somewhat fast and quick off the bounce one is highly effective.)

But key to this is to fake going crosscourt. It's only at the last second that you should tip your racket tip back from the forearm or wrist, aiming it to the right (for a righty), and take it down the line. Your opponent will be out of position, possibly over-anticipating a shot to his forehand, and will likely have to move back to his backhand, where he'll play a backhand shot instead of his likely stronger forehand.

For lefties vs. righties, there's a similar dynamic – fake down the line, then go crosscourt into the backhand. It's just as effective. In both cases, you've completely taken his serve advantage away, and forced your opponent to play a moving backhand. What more can you ask?

Ask ten people, and you might get ten answers. But there is a simple definition: a Good Serve is one that helps you win. Ideally, this would mean a serve that the other guy can't return – but if you can do that, your opponent isn't your level anyway. What you really want is a serve that sets up Your Game.

This means that if your best shot is a loop, then your serve should set up your loop as often as possible. If your best shot is a smash, then that's what your serve should set up. If you are more of a counterdriver, then that's what you want the serve to set up. And so on. On the other hand, what's a good serve for one player might not be a good serve for another. A short backspin serve might set up a looper who wants a push return – but it might not set up a counterdriver, who wants to get into a topspin-countering rally. A fast & deep serve might set up a hitter or counterdriver, but it might take a looper's best shot away. This doesn't mean a player should always serve the same way – but that they should favor the serves that will set them up.

You also have to take the future into account. If you are a blocker, you might win now by serving long over and over and letting your opponent attack so you can block. And while that might not be a bad tactic, strategically you might want to learn to serve and attack, perhaps by serving short, so you can add another aspect to your game. So you might want to develop serves that set you up to play the way you want to win in the future.

So develop lots of Good Serves, which set up your game now, in the future . . . or perhaps ones that just win you points directly from the sheer Goodness of the Serve. 

The key to deception on the backhand serve is the elbow. If you are serving backspin, you should vigorously contact the ball on the downswing, as much under the ball as possible, with a motion similar to chopping wood with a backhand motion. But the swing doesn't end there – you should follow through sideways and up by vigorously pulling up with your elbow. This forces the opponent to have to figure out if you contacted the ball on the down swing, or on the sideways or upward swing.

Similarly, when serving sidespin or side-topspin, you should start with this vigorous downward swing (chopping wood), as if serving backspin, but miss the ball, and instead contact it on the sideways or upward swing with that vigorous upward pull with your elbow. This time the elbow pull gives you spin instead of just being a fake motion. Again, the opponent has to figure out where you actually contacted the ball.

This principle actually applies to most serves, where your racket goes through some sort of semi-circular motion (often very short and abrupt, so opponent can't pick up the contact), where often are more vigorous on the part of the swing where you don't contact the ball. It's just a bit more obvious with the backhand, where much of the deception comes from the elbow. (But you still need a vigorous wrist motion for spin.) One advantage of serving backhand – you are facing your opponent, and so can see what he's doing as you serve. Some players can even change their serve, or at least service direction, in response to the receiver changing position at the last second.