You should shake cocktails like margaritas, daiquiris, and whiskey sours — which are typically accompanied by additives like egg whites, fruit juice, honey, or cream — to aerate the drink, making it look like it's been carbonated and creating a foam on top when high-protein ingredients are used. To shake correctly, mix your drink ingredients with ice into a two-piece Boston shaker, fitting it with a good hit from the heel of your palm.