Must be 21: Tequila goes best with citrus sodas such as Sprite or 7-Up; Fanta is another good citrus choice.
If you prefer cola, go for some Diet Coke with lime or lime Pepsi.
A real simple recipe with Fanta is 1-1/2 oz Jose Cuervo Especial gold tequila in 4oz of Fanta Orange Soda.
Another tasty recipe uses 1-1/2 oz of apple schnapps, 1-1/2 Jose Cuervo Especial gold tequila, 1/4 oz daiquiri mix, 7-Up. Fill a Collins glass with ice, pour in the liquors and then top with the soda.
Diageo, the world's largest spirits maker, was to buy a $3,000,000,000 stake in Jose Cuervo, however in mid December 2012 discussions collapsed, and Diageo pulled out of the deal.