Turning a screw clockwise (CW) is turning it to the right at the 12:00 position or “top of the clock” so to speak and generally tightens the screw. Turning a screw counter-clockwise (CCW) is turning it to the left and generally loosen the screw. Some screws on motors or shafts have what are called “reverse threads” where CCW tightens and CW loosens.