Final answer:
To signal a turn, push the turn signal lever down for a left turn and up for a right turn. This standard method is used in cars, motorcycles, and trucks to ensure safe communication with other drivers.
Step-by-step explanation:
To indicate a turn using a turn signal lever in a vehicle, you should move the lever up to signal a right turn and down to signal a left turn. The action is intuitive when you consider that you are indicating the direction relative to the driver's position. For example, when you want to turn left, you push the lever down towards the left side of the vehicle. Conversely, you push the lever up towards the right side of the steering wheel to initiate a right turn signal.
This maneuver is a standard across various types of vehicles including cars, motorcycles, and trucks. It's essential to know how to signal properly for safety and to communicate effectively with other drivers on the road. Remember, before making any turn, always ensure to signal in advance to give adequate notice to other motorists.