Examine the equipment and note where the pressure gauges and valves are.
Figure out which gauge measures the gas line pressure. This is usually written on the gauge.
Read the owner's manual to determine the correct pressure setting for the valve.
Set the pressure. Twist the adjustment knob in a clockwise direction until you have reached the necessary pressure as indicated by the user's manual. If you went too far, just turn the knob counterclockwise until you reach it again. Turning the knob clockwise will increase the pressure or open the valve, and turning the knob counterclockwise will lower the pressure or close the valve.