The Basic Return: I will start this section with a quote from Andre Agassi -

"My return is based 100 percent on a simple hip turn. Imagine the butt of the handle of your racquet is taped to your stomach, so the racquet points at your opponent as you face him. Now if you just turn your hips, your racquet is going to be prepared to hit the return. A good drill to teach a quick hip turn is simply to stand as if you're about to return serve and have somebody shout "forehand!" or "backhand!" and you react instantly with a hip turn, without a ball. The hip turn is an easy way not only to be prepared quickly, but also to keep yourself from swinging too big at a ball that you don't need to swing hard at." (Andre Agassi)

Agassi's article is a good example of how to prepare to turn your body to return the serve. Another good habit to get into is to step into the return of serve, just like your ground strokes. I have seen people backing up when trying to return a serve, but the best return will come when you are stepping into the court to return the serve. This technique will get you more pace and control on your return and you will also be cutting off the angle of the serve, making it less affective.

The Agassi Approach: Again I will turn to one of Agassi's articles to help you here. If I were to write this, it would sound similar, so maybe it will be more affective coming from the best returnee of serve ever! After the Agassi article I will continue to write on my own perspective... (Agassi article is in quotations below)

If consistency's your key, go for control on the return

Ask yourself: How do I win matches? If you play high-percentage tennis, breaking down your opponent with consistency until he makes an error, then I suggest you just try to get the return back in the court. For example, if I'm playing a baseliner, but I feel like I'm a stronger baseliner than him, I just think about hitting my return deep, not necessarily hard. If you're more consistent than your opponent, don't take chances on your return. Step back behind the baseline a couple of feet to give yourself more time. Don't lean too far forward on your toes; instead, keep your feet under you so you can move sideways easily. Don't cheat in one direction or the other; instead, look to cut off the highest-percentage angles of the serve so you can get your racquet on it to start the point. Remember: Simply getting a return back in the court can be a great weapon by itself, so don't feel bad if you're the kind of player who just does that and hopes for something better to happen on the next shot.

If power is your strength, be aggressive on the return

If you have a good serve and people have a hard time breaking you, then take chances on your return. Opponents will find it very difficult to face you with your big serve, knowing you also will be attacking their serve. That stress can cause them to make a lot of double faults. You also may need to be more aggressive on the return against a serve-and-volleyer. In this case, think about the height of your return over the net: You want to keep it low, so the serve-and-volleyer has to volley the ball up.

Give the server something to think about

If you have one return that's better than another-if, say, your forehand is better than your backhand-or your opponent has one serve that's less effective than another, don't be scared to change where you stand in order to play to your strengths and his weaknesses. Unless you're completely handling his serve as it is, give the server different looks. Get him thinking about what you're doing.

Make a big server pay for a second serve

If your opponent has a big first serve but not that great a second serve, don't worry about his first serve! I sometimes guess on the first serve of a huge server like Mark Philippoussis or Goran Ivanisevic; I may lean a little one way or the other, though I don't make a full commitment in one direction. But when a big server misses his first serve, I try to really hurt his second. This could be by getting it back deep and then working him left and right and getting him tired. Or it could be by really whacking the ball if I get a good look at it. Make a big server pay for a second serve, so he feels the pressure of having to make his first. This can hurt his serving percentage and is one way a good return can change the whole tone of a match.

Footwork and Preparation:
Footwork and preparation play a large role in the return of serve. Always step into the return if possible; stepping backwards to hit any shot can prove to be a bad situation. You also need to prepare early! Be ready to split step and bring you racquet back early. Split stepping once the opponent is about to strike the ball will keep you on your toes and ready to go either direction while bringing you racquet back immediately after the ball is hit and you see what side it is coming to, gives you more time to prepare. I find that bringing the racquet back early when the opponent hits a fast serve makes the ball seem like it is moving slower because it gives that essential preparation time.

Be sure to work on your return so you can make the serve less of a weapon for your opponent. You return serve as much as you serve if not more (in doubles) so it should demand as much practice and attention as your serve.