I don't do that every day, but have done it as part of foreplay.
Starting with her laying face down on the bed so I can give her a massage first, letting my fingers periodically stray towards her bottom. I'll eventually lightly trace my fingers between her legs but just brush beside her pussy and asshole, not touching them yet. At that point I will start licking lightly at the top of he butt crack, fingers still between her legs as described earlier. Building that anticipation for her, when I make that first light probe of my tongue at her asshole she moans with delight. After licking her asshole for just a short bit I will finally finger her clit, and it doesn't take her long to cum after that.
For anyone who has never licked a woman's asshole, assuming she's clean, there is no unpleasant odor or taste. It will be a new adventure for both of you.