When to rinse
Rinse when a small amount of a forceful spirit should frame the drink — Sazeracs (absinthe), some smoky variations (mezcal or peat), the occasional bitter rinse. You’re seasoning the glass, not adding an ingredient to the mixing tin.

Technique
Coat the inside of the glass with a small amount of spirit (often absinthe), then discard the excess.
The big idea
A rinse coats the glass with a few drops of a loud spirit — aroma and a light accent — then the excess goes down the sink so it doesn’t become the drink.
Pour a splash, tilt to coat, discard the extra.
Absinthe, peaty Scotch, and mezcal are the usual rinses — intense bottles used as perfume.
Chill the glass first so the film clings instead of pooling.
If you can taste a full measure of the rinse, you didn’t dump enough.
A rinse is not a float; it lives on the glass, not as a layer on the liquid.
Rinse when a small amount of a forceful spirit should frame the drink — Sazeracs (absinthe), some smoky variations (mezcal or peat), the occasional bitter rinse. You’re seasoning the glass, not adding an ingredient to the mixing tin.
Pour a splash in glass
A barspoon or two of absinthe, vermouth, or liqueur.
Tilt to coat sides
Roll the liquid around the inside of the glass.
Discard excess
Dump what doesn't stick — you want perfume, not volume.
Add a teaspoon or so of the rinse spirit to a chilled glass. Tilt and roll until the inside is coated. Dump the excess (or, if you prefer a slightly louder glass, leave a few drops).
Strain the finished cocktail into that glass. Garnish as written — often an expressed peel on top of the rinse aroma.
In the glass
Open a recipe, focus on this move once, then make it again next week.