How do you signal a left turn while driving?

To signal a left turn while driving, the correct method is to extend your left arm straight out from the driver's window. This hand signal clearly indicates your intention to make a left turn to other drivers and pedestrians. It is a universal gesture recognized by road users, providing visual communication while you are in the process of turning, especially in situations where turn signals might not be visible or operational due to a malfunction.

Using arm signals is a fundamental part of driving etiquette and safety, ensuring that everyone is aware of your intended actions on the road. Though using a vehicle's left turn signal is effective, the hand signal serves as an additional means of communication and can be particularly useful in circumstances such as in older vehicles without functioning electronic signals or when turning in heavy traffic.

The other options, while they might seem plausible, either represent incorrect gestures or do not reinforce signaling with an arm for a left turn. For instance, waving a hand in front of your vehicle is not a recognized signal, and extending the right arm would indicate a right turn instead. Therefore, extending your left arm straight out is the standard and recognized way to express the intention to turn left.