Today I'm not going to be discussing what you may think from reading the title. I will not be talking about the 'T' in the middle of the court. Instead I'm going to talk about the imaginary 'tee' that I try and place the ball on before I hit each shot. You physically do in golf or tee ball in baseball, while playing squash if you can hit the ball off of this imaginary tee more often than not you will play better and hit more consistent shots. If you could put the squash ball on a tee before you hit it, where would you position yourself relative to the ball? Let's find out where to set up and how to do this in a game.
The first step is knowing where about you want to hit the ball relative to your body on your forehand and backhand. This will differ slightly for cross courts, boasts, and so on. To keep things simple I'm going to use the straight drive as an example. On the forehand side you will probably hit the ball a little behind your lead foot when you are stepping with your front foot (conventional footwork or closed stance). If you hit your forehand with an open stance (on your back foot) you will aim to strike the ball parallel to your foot. We use these spots as frames of reference between body and the sidewall so that we can accurately hit the ball parallel to the sidewall. Squash is a game of inches and hitting the ball a half inch too early or too late will end up spraying the ball into the middle of the court.
On the backhand side, when you hit a drive from a closed stance (front foot) you want to hit the ball parallel to your foot or slightly on the edge closer to the front wall. Top players are just as comfortable hitting off of their back leg (open stance) on the backhand and when they do this will try and hit the ball at the back foot.
Knowing where you want to place the ball to hit it straight down the wall is crucial. But you also need to get the spacing between you and the ball correct. Just like in golf, if you're too far away or too close (which is most common in squash) you will be unable to take an optimal, full and fluid swing. You may be off-balance and unable to transfer your weight properly into the shot. This is even more important on the backhand side of the court as it's much more difficult to hit the ball when it gets just a bit behind you (as opposed to the forehand side). Your spacing depends on the height of the ball you are striking. I like to get low to the height of the ball, so I don't just drop my racquet head to hit a low bounce. I keep my hand and grip at least the same height as the ball or slightly below. If you follow this rule you will keep better spacing. This also means the taller you are the lower you have to get your hips and bend your knees.
So if you can visualize where this spot is you can begin doing simple repetitive drills and attempt to hit more consistently off of the 'tee' and you will be hitting the ball straighter, with more consistency and with more power. You should build up your drills from basic repetitive drills to more complex and random ones. This will make it much more challenging to get the ball on the tee. A lot of this has to do with footwork (spacing), judging the receiving ball, and racquet preparation (shaping). To me these are the two most important skills in squash. If you do these well you will be successful.
This paragraph is more for advanced players but is also something I like younger kids to think about. Advanced players seem like they consistently tee up the ball and hit the middle of the strings. Besides hitting more consistent, the relative ball location (the imaginary tee) has a lot to do with disguising your shot, deception, and anticipation. Once you can consistently put the ball on the tee you should begin thinking about how to couple shots. Can you hit 2 or 3 or even 4 shots from the same relative ball location, from the same spot you've tee'd up the ball? This is why a disguised attacking boast and trickle boast can be so effective. The player shapes up like a drive and are spaced the same, the only difference is late in the swing they are able to withhold excessively supinating their forearm and extending their wrist until just after ball contact. This means the racquet face is closed at impact and the ball goes into the side wall first. The same thing can be done at the front of the court to disguise your straight and crosscourt drives. It's usually quite obvious when someone is going to hit crosscourt because when they start their downswing the ball is well in front of them making it quite difficult to straighten the ball.
How consistently do you hit the sweet spot on your racquet? Think about 'teeing up' the ball the next time you play and you may just start squaring up more shots. Professionals have this tee perspective for all shots and have the racquet skill and agility to make adjustments when they're not. But even pros lose consistency when they don't hit the ball from the tee or the sweet spot. This is why the shot down the middle and clinging drives work well at every level.