Prep your garnish. With a vegetable peeler, remove a strip of peel from an orange. Set aside. (If you are using an orange wedge, slice off a thin piece of orange and set aside.)

Mix your drink. Fill a tall mixing glass halfway with ice. Add the gin, Campari, and sweet Vermouth, then stir everything together until the liquid is cold, 30-40 seconds.

Pour. Add ice cubes to a lowball glass, then strain the drink into the glass.

Garnish and serve. Run the inside of the orange peel around the rim of your glass, then garnish the drink with the peel. If you’re using an orange wedge, similarly run the wedge around the rim of your glass and then garnish the drink.