Add the margarita ingredients and a handful of ice cubes to a cocktail shaker. Place the lid and cap on the shaker and shake a few times to combine.
2 oz fresh orange juice (1/4 cup), 1 oz fresh lime juice, 1.5 oz tequila blanco (1 standard shot glass), 1.5 oz Cointreau (1 standard shot glass), ½ to 1 oz simple syrup (1 to 2 tbsp), Ice