Remove seeds from the pomegranate. Place in a large mixing bowl and mash with a potato masher until mostly broken down. The goal is to remove as much pomegranate juice as possible.
Strain pomegranate juice through a fine mesh colander.
Combine roughly ¼ cup (65 grams) sugar and roughly ¼ cup (65 grams) pomegranate juice in a small sauce pot. Place on the stove over medium heat. Stir occasionally until sugar is completely melted. Refrigerate until cooled.
Sprinkle enough sugar to coat a plate. Lightly wet a paper towel or cloth. Run along the rim of a cocktail glass to wet. Place the glass rim in the sugar to coat.
To make four drinks: Combine 8 ounces gin, 3 ounces of the pomegranate simple syrup, 3 ounces lemon juice in a cocktail shaker. Shake to combine. Pour over ice. Add ½ ounce seltzer to each drink. (There should be about 1 ounce of simple syrup left over).
To make one drink: Combine 2 ounces gin, ¾ ounce simple syrup, ¾ ounce lemon juice in a cocktail shaker. Pour over ice. Top with ½ ounce seltzer.
Pomegranate: An equal amount of pomegranate juice can be used in place of prepping your own pomegranate.
Gin: Each cocktail will have 2 ounces of gin. Decrease to 6 ounces gin for a lighter drink (1.5 ounces per drink).
Seltzer: Plain seltzer also works. I like to use orange seltzer for a light orange flavor.
Microwave simple syrup: Transfer sugar and juice to a small microwave safe bowl or cup. Microwave for 30 seconds to a minute, or until whisking causes the sugar to dissolve.