This is probably my favourite cocktail.
This is how I make them.
Optional: Prepare glasses
Pour some salt onto some waxed paper.
Wet the rim of a glass with lemon or lime juice.
Turn the glass upside down and put it on the salt.
With a circular motion, move the glass around in the salt until the rim is coated in salt.
If you like your Margaritas very cold, chill the glass by filling it with crushed ice and water. Empty the glasses right before pouring the Margaritas.
Put the following in the top of a cocktail shaker or in a glass:
4 parts tequila
2 parts triple sec*
1/2 part lime juice
1/2 part lemon juice
Put ice cubes in the cocktail shaker.
Pour the liquids into the shaker. Put the top on the shaker. Shake. Strain the Margarita into glasses.
* If you want a slightly smoother Margarita, use Cointreau as your triple sec. We prefer the generic triple sec. It has a little more "bite".
Here's a somewhat fuzzy photo of Margaritas and ABTs that I made last March.