Locate the low speed idle adjustment screw access on the right side of the Stihl chainsaw and place a screwdriver through the access hole in the handle in front of the screw access.
Turn the low speed screw clockwise with the screwdriver until you can feel resistance without over-tightening to start the adjustment. Adjust the low speed screw by turning it counterclockwise one complete turn with the screwdriver.
Start the chainsaw and let it warm up for a few minutes. Locate the idle speed adjustment screw just below the low speed screw on the chainsaw.
Turn the idle speed adjustment screw clockwise with a screwdriver until you hear the chainsaw start to stall and turn the screw back counterclockwise one quarter of a turn.
Adjust the idle speed screw by turning it counterclockwise until you hear the engine begin to stall and turn the screw back clockwise one quarter turn.
Complete the adjustment by turning the low speed screw counterclockwise until you hear the chainsaw running smoothly and shut the motor off.