1: Perform the 3 initial clicks, with the first click kissing your camera lens and the later two clicks as far back as you can step while still getting the crosshairs
Now to start refinement.
Note: If you can't reach all 3 crosshairs the next steps will take more time, but if you repeat steps 2 through 6 you will eventually get a solid calibration
2: Step close to the camera, hold your controller up near the center of the frame and adjust x/y/z, try to adjust the Z so that the controller matches IRL size
3: Step back really far and adjust pitch and yaw with your hands out, try to get one controller close
4: Hold both controllers out to the sides, if the controllers are too far away on the inside/outside you need to adjust your fov
5: Step close and hold your controllers out to the sides again, adjust fov if necessary
6: Step in the middle and hold the controllers out to the sides, try to adjust the rotation so they look even
7: Repeat step 2 through 6 until your controllers are really accurate no matter where you are in the frame