Don’t assume the customer is fine with the substitute. Let them know you would have to use a soda replacement, and give them the option to change the order.
Bitters are alcoholic. Skip this step if you’re making the drink for kids or non-drinkers.
Make simple syrup by combining equal amounts of sugar and water. Heat and stir until all sugar is dissolved, then let cool. To make sour mix, combine two parts simple syrup and three parts lemon or lime juice. [1] X Research source
Heat 1 cup (240mL) water and 1¼ cups (240g) sugar, stirring until dissolved. Add ½ cup (120mL) grated or thinly sliced, raw ginger. Simmer for 15 minutes. Let cool, then add 2 tbsp (30mL) lemon juice.