Never change lanes in traffic without:

• Only looking in the rear view mirror
• Giving proper signals and looking to make sure the move can be made safely
  Explanation:

  "Before changing lanes, always signal to alert other drivers of your intentions. It’s also critical to check your mirrors and blind spots to ensure the lane change is safe. You should also be aware of your speed and maintain control of your vehicle while making the lane change."
• Blowing your horn and looking to the rear
• Decreasing speed and giving correct signal