Once a basic color is determined, now comes the fun and creative part. She may suggest adding lighter highlights around your face and maybe even dispersed throughout your hair. Lighter color near your face can change your entire appearance without the permanent commitment of an all over change.
Another thing that's changed from when your mom used to color her grays away under the cover of darkness is the quality of the products available. It's been a long time since anyone has gotten even a whiff of any strong, offensive smelling products in salons. Those have long since disappeared or been replaced by gentler formulations that are free, or mostly free from ammonia, peroxide or other harsher chemicals.