Good grooming starts with proper lighting at the mirror. The important thing to remember is to light the face, not the mirror. In a perfect world, the light should come from both sides as well as the top. The illumination should be soft and shadow free to make grooming easy and comfortable.
For ample light without glare, choose a shielded fixture. To obtain a sparkling effect, use clear cut-crystal glass but with lower wattage or dimmed lamps.
Naked bulbs on the top or sides of a mirror may look rather glarey, but in low wattage, they can be a good accurate makeup light (although certainly not my choice.)