Chapter 30: Freeway Lane Changes
The Full Check
Before any lane change: check your mirrors, then physically check your blind spot by glancing over your shoulder, then signal for at least five seconds before actually moving over. Mirrors alone cannot cover the full blind spot next to your rear quarter panel.
Lane Discipline
Keep right except when passing — the leftmost lane is meant for overtaking slower traffic, not for cruising, and lingering there forces faster traffic to pass you on the right, which is more dangerous than a standard left-side pass.