Connect to the Tank: Ensure the CO2 cylinder valve is fully closed. Thread the regulator onto the tank securely using an adjustable wrench to create a tight seal.Back off the Adjustment Knob: Loosen or un-screw the regulator’s main adjustment knob (counterclockwise) so no spring pressure is applied.Turn on Gas: Slowly open the main CO2 tank valve counterclockwise until fully open. The tank pressure gauge will now register.Set Output Pressure: Turn the adjustment knob clockwise slowly until the low-pressure gauge reaches your target PSI.