Popsugar, Absolut and Drinks Mixer provide good recipes for the Singapore sling. The Popsugar recipe closely mirrors the original recipe for this tropical cocktail, while Absolut and Drinks Mixer provide less complicated versions.
To make Popsugar's Singapore sling, add 2 ounces of gin, 3/4 ounce of Cherry Heering, 2 teaspoons of Bénédictine and 2 teaspoons of orange liqueur to a cocktail shaker filled with ice. Add 2 ounces of pineapple juice, 3/4 ounce of fresh lime juice, 2 dashes of grenadine and 1 dash of Angostura bitters. Mix the ingredients, strain the cocktail into an ice-filled glass, and top it with a splash of club soda. Garnish the cocktail with a twist of orange, a sprig of mint, and a maraschino cherry.
Alternatively, make Absolut's Singapore sling recipe by combining 2 parts of gin, 2 parts pineapple juice, 3/4 part cherry liqueur and 3/4 part lemon juice in a shaker filled with ice. Add 1/4 part triple sec, 1/4 part grenadine and two dashes of bitters. Shake the mixture, and pour it into a glass filled with ice. Top it with soda water, and garnish it with an orange slice and a cherry.
To Drinks Mixer's simplified version, add 1/2 ounce of grenadine to the bottom of a glass. Fill it with ice, add 1 ounce of gin, and nearly fill the glass with equal parts of club soda and sour mix. Top it with 1/2 ounce of cherry brandy.