How to set your mirrors.

Here is a handy and quick way to set the mirrors for most cars courtesy of our friends at the U.S. National Safety Council:

From your normal position in the driver's seat, lean your head against the driver's side window, then turn the driver's side mirror so that you just barely see the side of your car.   Once this is set, move to the center of the vehicle and turn the passenger side mirror so that you can just barely see the passenger's side of your car in the mirror.   That's it!

You can view the entire excerpt here Set My Mirrors.

When set correctly the mirrors should behave as shown below. If the above technique doesn't work for you, follow the detailed procedure shown here:

Start by setting yourself up in a parking lot by pulling into a parking space with cars parked on the other side of the driving lane behind you.

Then...

Note the position of the driver's side reference vehicle in rearview mirror.	Adjust side mirror to show what rearview does not.	Note the position of the passenger's side reference vehicle in rearview mirror.	Adjust side mirror to show what rearview does not.
This is how it works... Car overtaking is leaving rearview mirror field of view.	At the same time the overtaking vehicle becomes visible in the side mirror.	As the overtaking vehicle disappears from the rearview...	...it becomes fully visible in the side mirror.
As overtaking vehicle leaves field of side view mirror it becomes visible in peripheral vision.	It works the same on the passenger's side... Car overtaking is leaving rearview mirror field of view.	At the same time the overtaking vehicle becomes visible in the side mirror.	As the overtaking vehicle disappears from the rearview...
...it becomes fully visible in the side mirror.	As overtaking vehicle leaves field of side view mirror it becomes visible in peripheral vision.

If the mirrors are set correctly the angle of the overtaking vehicle doesn't matter. In other words, if there is one passing lane or five, the mirrors still work the same way.

Note that you cannot see directly behind you with the side view mirrors. That's not what they were made for, they should only show objects to the side of the car.