First, in a pitcher, mix together the lime juice, sugar, and water until the sugar is dissolved, then add the rest of the ingredients. Rub the rims of the margarita glasses with the cut side of half of a lime. Dip the rim into coarse salt or sugar to garnish. Fill your cocktail shaker with ice, add about half the margarita mixture, then shake for about 15 seconds or until the mixture is chilled. Strain into the glasses. Garnish the glasses with a slice of blood orange or a slice of lime if desired and serve!