Fill a highball glass with ice cubes. Add all ingredients and stir. Garnish with a grapefruit wedge.
• Use a tall glass / highball glass rather than a short glass. That ensures that the drink stays carbonated for a longer period of time.
• Make sure to use plenty of ice in the glass. That will keep your drink colder, crisper and fizzier longer.
• Balance and proportions are key. A good ratio is 1 part vodka to 3 parts tonic.
• Garnish the drink with your favorite fruits and berries in season to give it a fun twist.