Have you ever had to use your mirror to see something on the back of you? Well, you could always turn around, and then try and swivel your neck as best as you can. Or you could take a hand-mirror and try and get the reverse angle. Sometimes one of those methods works.
Or you could get the 360-Degree Mirror. Three panels on each side pop out so you can get more views of you. There is also a light on the front for a little extra glow. You might want to use the lighting to see what your “best side” is.