If you are making a cocktail that requires muddling, for example crushing your strawberries with lime and simple syrup, this is done first before it goes into the shaker or topped up with other ingredients. In the shaker, there is no set order, so all ingredients can go in at the same time. If you are pouring a spritz or champagne cocktail, the fizzy element is added straight to the glass last to ensure the person sipping gets all the bubbles.