A brief explanation on how to drink Tequila the tourista way.

[edit] Steps

Slice a regularly sized lemon or lime into eight small pieces.
Fill a shot glass with tequila.
Briefly lick the skin between your thumb and forefinger, then sprinkle 1 small pinch of salt (kosher salt melts quickly) onto the area. The lick makes it stick.
Using the same hand that contains the salt, you must hold one slice of the lemon (or lime) with your thumb and index finger.
Quickly lick the salt, down the tequila, and bite the lemon (or lime). Swish it around in your mouth for a couple of seconds and then swallow.
Enjoy!

[edit] Video

[edit] Tips

Remember, Lick-it, Slam-it, Suck-it! (Salt first, tequila second, lemon/lime last).
For a fun variation, ask a gentleman- or lady-friend to lend his or her hand (or other part) for the salt.
If you purchase good tequila such as Patron, Sauza Tres Generaciones Plata, Chimayo, or Don Julio Anejo, salt and lime are not needed, and tequila experts may become upset at these ingredients being added.
Quality Tequilas are like quality Scotch. They aren't meant to be gulped, but rather sipped and savored.
As said above, this way of drinking tequila is meant for low quality brands, in order to mask the horrible taste and the funny aftertaste. Also it is meant to create a trend, as it has a lot of bells and whistles. If you have in front of you a good bottle of tequila, take your time to appreciate it.
Mexicans and experienced tequila drinkers often refer to the lime and salt combination as "training wheels".
One may wish to attempt the "Tequila Ironman." This involves snorting the salt, taking the shot, and squirting the lime in your eye, followed by a smack in the face from the friend with whom you are taking the shot. Shirt must taken off for the Tequila Ironman to count.
Another way to take a tequila shot involves putting a dash of tobasco sauce into the tequila shot. This sinus-clearing shot is referred to as "the Prarie Fire."
It is also possible to attempt the "Tequila Strong Love". One person takes the salt in his/her mouth, and then makes out with the drinker. After that the person takes the lime in his/her mouth, a bit stuck out, so the drinker can easily bite it. Take it easy, as it is easy to miss the lime and bite the tongue instead.

[edit] Warnings

Drink responsibly!
Not drinking responsibly can cause serious injuries.
This way of drinking, specially if low quality tequila is involved, can lead to a long talk with the toilette.
Take pauses between shots to see if you can take the next one.