Things You'll Need
Pencil and paper
A bathroom vanity isn't complete without a light over it. It's important to choose not only proper lighting that helps you see while applying make-up, styling your hair or shaving, but also lighting that fits properly over the mirror. A light that is too large can cause a glare and one that is too small will not properly illuminate the room or your face.
Measure the width of the mirror and write the measurement down.
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Measure the space between the mirror and the ceiling. If it isn't a large space, you must be certain that there is room for the fixture. Most light bars require at least 6 inches between the top of the mirror and the ceiling for proper installation.
Strike a line with a pencil about 2 inches above the mirror, across the top. Strike another line, parallel and above the first, to indicate where you will place the light bar.
Measure your light bar and make sure it isn't too long for the mirror or too wide for the space between the mirror and the ceiling.