What action should you take before changing lanes?

Before changing lanes, it is crucial to check your mirrors. This action allows you to assess the traffic around you, ensuring that it is safe to make the lane change. By checking your mirrors, you can identify any vehicles that may be in your blind spots or approaching quickly from behind, which is vital for avoiding collisions.

While adjusting your speed may be necessary in some situations, it does not directly contribute to ensuring a safe lane change. Turning on your headlights is not a requirement for changing lanes unless visibility is poor, and signaling your intention is important but comes after ensuring the lane is clear. Therefore, checking your mirrors is a fundamental step that prioritizes safety and awareness before initiating the lane change.