I'd approach things slightly differently, as if you follow the directions above, you are using the microswitch to stop the travel of the trigger, and over time, you can damage the switch.
Briefly, it is worth mentioning the available trigger adjustments - this is assuming you have the stock trigger.
You have one trigger stop screw through the top of the trigger, a microswitch actuation point adjustment screw through the back of the trigger (top screw), and rear trigger stop through the back of the trigger (bottom screw).
The screw in the top of the trigger is described in the manual as being a return force adjustment, and that is vaguely true in an indirect sense - by changing the angle of the trigger, it could be argued that leverage has changed, and hence the force required to pull the trigger has changed. However, you aren't actually changing the distance between the screw and the magnet, so the actual force of attraction between the screw and magnet remains the same. In practical terms, it's adjusting the starting point of the trigger in it's arc of movement, so I would describe it as a front trigger stop.
Having got that out of the way, here's what I would do.
Initially, back out the witch actuation screw - don't want to risk crushing your switch while you are tinkering with the trigger stops. I would then adjust the front trigger stop to get the trigger positioned where you want your trigger pull to start. Then adjust the rear trigger stop to set your overall trigger pull length. Finally, adjust the actuation screw so that the marker fires at the point in the trigger pull that you prefer. I like a little overtravel, so I normally set the firing point 2/3-3/4 through the pull.
Again, having set your firing point - and particularly if you have a fair amount of overtravel - be careful to ensure that the trigger is stopped by rear trigger stop rather than hitting microswitch.