WITH ALCOHOL
Simple sugar mixture (1/3 cup of sugar and 8 oz water)
1/2 capful Cointreau
1 oz tequila (mid-priced, avoid the cheapo stuff)
Juice of 1 lime
In a highball glass, rub the squeezed lime peel on the rim. Salt the rim. Mix Cointreau, tequila, and lime juice. Fill the highball with ice and top with the simple sugar mixture.
WITHOUT ALCOHOL
These can be made without alcohol! Just use the simple sugar mixture, the juice of 1 orange, and the juice of 1 lime.
Also, just make 1 margarita at a time to keep the quality of the margarita awesome!