Instant Docking Tutorial:
Fit an Automatic Docking Computer and let it fly your ship through the mail-slot a few times, taking note of where and how high it lines your ship up as it passes through the slot. If you emulate the docking computer you should have no problems. Why not use the docking computer all the time then? Well, it uses up a slot and takes much longer to dock your ship. It also crashes your ship into the station walls and kills you about once in ten attempts.
Simply practice, "Git Gud" at landing and pretty soon you can do it in your sleep.
A couple of notes on docking the bigger ships:
In an Anaconda, go through the slot really, really high like if you are not instinctively ducking your head as your Annie goes through the slot, then you are still too low. The Annie is a big, bridge-on-top ship and the transition from the smaller ships can be difficult. All the rest of the ship is under you so go through the slot really high. You can go through pretty far to one side, too as three Annies can pass through the slot side by side.
In the Corvette, your course is right down the middle, still high but not as high as the Annie. The Corvette is also a "bridge-on-top" ship, longer and wider than the Anaconda but not as tall and so has a little more leeway when it comes to how high you go through the slot.
In the Type-9 (and Type-10) everything noted about the Corvette (above) is true and additionally the T9 is a big, lumbering, slow ship that cannot get out of anything's way so be extra careful about traffic. That being said, I have gone through the mail-slot in an Anaconda with a T9 coming the other way and while we traded paint, neither crashed or got stuck.
In the Cutter, the bridge is out at the very front of the ship but a bit lower and with the bridge set lower relative to the rest of the ship you need to pass through the slot a little bit below center in height because there is still quite a bit of ship above you. Left to right though, you need to go right down the middle. "Make way for larger vessels"? You ARE the larger vessel but other ships will not get out of your way so you need to keep an eye on traffic to avoid getting caught in the mail-slot with another large ship coming the other way. You have several minutes after launching to exit the station so take your time, check your sensors, see what other ships are coming through the slot and time your exit accordingly. Also, when entering stations, with that out-front bridge you need to remember the entire rest of the ship is still behind you. Drag the rest of the ship through the slot before maneuvering toward a landing pad.
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