Take a cocktail shaker and place ice cubes in it according to your requirement.
Now, top the ice cubes with 2 oz of gin, 1 oz of lemon Juice, and 1/2 teaspoon of superfine sugar.
Cover the cocktail shaker properly and shake it for few second until the sugar dissolves well.
Grab a cocktail glass and pour the drink into it.
Garnish your Gin Sour cocktail with Maraschino Cherry or a fresh lemon wedge and serve chilled.