Ice. It all comes down to the ice. • Dry shaking involves shaking with no ice at all. These cocktails are then poured into a glass either straight up (no ice) or over the rocks. • Wet shaking includes ice in the cocktail shaker. These cocktails can also be served straight up or over additional ice in the glass. For Whiskey Sours, in particular, I recommend dry shaking and then pouring over ice. Unless you are using egg whites, then wet shake and serve straight up!