First, loosen the counterscrew, focus stopping screw and the two screws to the left and right
of the tension adjustment screw in the middle of the crayford focuser bearing plate. Then
tighten (or loosen) the tension adjustment screw, so that the focuser tube does have a good
grip and does not slide by itself. Now, carefully tighten the the two screws left and right of the
tension screw, they are here to exactly parallelize the teflon bearing to the crayford shaft and
to limit the pressure of the tension screw.. Do not really tighten them, they should just touch!
Now you may tighten the tension screw a little more and counterbalance it with the two
screws left and right. You can put a tiny amount more pressure, because in the final part
you may regulate that with the counter screw, placed in the middle and near to the
telescope tube.

See attached pdf document for further details, photos etc.