What is the first step to take when changing lanes?

The first step to take when changing lanes is to check traffic ahead through both rearview mirrors. This crucial action ensures that the driver is aware of the current conditions surrounding the vehicle. By checking the mirrors, the driver can gauge the speed and distance of vehicles behind and adjacent to them, providing a broader understanding of the traffic situation. This assessment is essential for making safe decisions about whether it is clear to change lanes.

Following this, signaling intention to switch lanes, inspecting blind spots, and adjusting speed are also important steps. However, they should occur after confirming that it is safe to change lanes based on the information gathered from the mirrors. Thus, utilizing the mirrors first allows for a systematic and safe approach to making a lane change.