Add the pineapple juice, non-alcoholic rum, lemon juice, and blue curacao syrup into your cocktail shaker along with a handful of ice. These four ingredients are what build the flavor and that unmistakable glowing color everyone notices first.
Close your shaker and give it a good, firm shake for about 15 to 20 seconds. You'll know it's ready once the outside of the shaker feels ice-cold and slightly frosty to the touch.
Strain the mixture into a highball glass filled with fresh ice. Straining keeps any small ice chips out, so what you're left with is smooth and perfectly chilled.
Finish the drink by topping it off with a splash of club soda. This adds the fizzy lift that makes the whole thing feel like a real party drink instead of just juice.
Give it one gentle stir to bring the fizz and juices together, then serve right away while it's still bubbling. This mocktail is best enjoyed fresh, before the ice has a chance to water it down.