My Sodapop Sharon UP Mode D'emploi page 38

Place carbonating bottle cap and tighten. Gently roll or shake the
bottle to ensure the essence is thoroughly combined with the
carbonated water. Allow it to settle for a few moments and carefully
unscrew the cap. You may find that – after having shaken your soda –
it may be extra-sparkling as you open the bottle. Try twisting the cap a
quarter-turn to release pressure, and then quickly tighten again before
opening all the way.
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