To cocktail shaker, add lemon juice, lime juice, ginger simple syrup, gin, and ice. Shake vigorously for about 5 seconds. Pour into a Collins class and top with seltzer. Garnish with a lime or lemon wedge.
If you do not own a cocktail shaker, you can use a mason jar or stir the items in a tall glass. It's cool. Just make the cocktail!