The collins is a classic cocktail with a confusing past. The original was named for its creator, John Collins, who worked as a bartender in a London hotel during the early 19th century. His recipe, which combines dry gin, lemon juice, sugar, and club soda, is identical to a fizz, except that it is served in a tall collins-style glass with an orange wheel or cherry garnish. It’s also closely tied to the sour, but includes club soda.

Learning to perfect a classic like the collins is a great way to build skill…