Add the tequila, triple sec (or cointreatu) and cranberry juice to a small pitcher or cocktail shaker.
Roll the limes (see above), then cut them in half and juice two of them into the pitcher or cocktail shaker. Stir or shake to blend. Slice the remaining lime into wedges.
To rim the glass, pour the salt onto a small shallow dish. Run a wedge of lime (from the remaining lime) around the edges of two glasses then dip the glasses into the salt gently pressing so the salt sticks to the rim.
Fill the glasses with ice being careful not to disturb the salt then pour the Christmas Margarita into the glasses, garnish as you like and enjoy right away!