(1) Start with ice cold ingredients or combine them in the Drinkmate bottle and freeze until very well chilled.
(2) Carbonate according to Drinkmate instructions, by pressing down the button until you hear gas escaping. Use the release valve to allow more gas to escape and the drink to foam up, then repeat the carbonation process.
(3) Once you've carbonated a second time, allow the drink to settle for a minute before releasing the pressure very slowly. You want as little foaming as possible this time, which means the more slowly you release pressure the better.
(4) Open and pour gently down the side of a champagne flute chilled in the freezer. If you choose to serve over ice with an orange slice, use a large ice cube and balance the orange on top.