Be extra cautious when changing lanes on a freeway. On multi-lane roads you need to check that the lane is clear before you enter it and you also need to check to make sure someone from another lane is not moving into that spot. 

Because traffic moves so quickly on a freeway, it is especially important that you let vehicles behind you know that you intend to change lanes. Once you have made certain that a lane is clear, signal early and increase your speed slightly as you move into the lane. Watch to make sure that any vehicle behind you does not speed up. 

When passing an entrance ramp where other vehicles are merging onto the freeway, move to a lane as far away from the entrance ramp as possible. This will help you to avoid being hit by drivers who do not see you and merge into your lane or move over to let merging traffic enter. 

Do the same thing at exit ramps. If you are driving in the lane closest to the exit ramp, you may be cut off by a driver who does not see you and cuts across the lane in front of you to get to the exit ramp.