Before making a lane change, what must a driver always do?

When preparing to make a lane change, the most crucial step for a driver is to signal their intent clearly. This action communicates to other road users, including drivers and pedestrians, that you plan to change lanes, enabling them to anticipate your movements and make necessary adjustments to maintain safety. Signaling is not only a courtesy but also a legal requirement, helping to reduce the chances of accidents caused by miscommunication.

While it's important to check mirrors and be aware of pedestrians, signaling specifically conveys your intentions to others, making it the most vital step in the lane-changing process. Other options that involve reducing speed, checking mirrors, or exclusively looking for pedestrians, while important safety measures, do not replace the necessity of signaling. These actions, although relevant, serve more to ensure that the lane change is safe after you have communicated your intentions.