How do I make sure the CO2 regulator is installed correctly?

Nat

Check gauges on CO2 regulator are on ‘zero’. If not, try to release residual air by pulling safety release valve.
Do not screw on the control knob yet. If the CO2 gauge keeps going up despite no control knob installed, the regulator is faulty.
Connect the regulator (without control knob) to the CO2 cylinder. Make sure red lever is in the ‘off’ position (horizontal).
Turn the cylinder valve ‘on’, then check the connections for leak using soapy water. Tighten with a wrench until no leak is observed.
Screw on the control knob and gradually increase to desired pressure. making sure the red lever is still closed