What you need to do is:
1) set the bias (aka "anti-skate") to zero. This is the dial just below the arm-rest.
2) Now, turn the whole counterweight (ignore the dial markings for now) until the arm balances or "floats", which means the downforce is set to zero. Next, move the dial ONLY (it turns separately) until "0" is at the top. Finally, turn the whole counterweight so that it moves nearer the arm pivots, until the desired figure (1.75 by the manual, 1.8-1.9 if that's your preference) is at the top on the dial. This should give you the correct downforce/ tracking force.
3) Now you can set the bias/ anti-skate on the other dial to the appropriate figure - about the same as the downforce is a good starting-point, though many like to use a bit less.