What cocktails can I make with tequila?

Margarita (with Cointreau and lime), Paloma (with grapefruit soda), Tequila Sunrise (with orange juice and grenadine), and tequila Old Fashioned variations. Blanco tequila is the canonical mixing choice.

Tequila is most associated with the Margarita but works in a wider range than people expect. With just blanco tequila and pantry items: (1) Margarita — 2 oz tequila, 1 oz Cointreau, 1 oz fresh lime juice, shaken, salted half-rim, served up or over rocks. The IBA spec. (2) Paloma — 2 oz tequila, 0.5 oz fresh lime juice, 4 oz grapefruit soda (Squirt, Jarritos, or Fever-Tree pink grapefruit), built in a highball over ice with a salt rim. The Paloma is actually more popular in Mexico than the Margarita. (3) Tequila Sunrise — 1.5 oz tequila, 4 oz orange juice, 0.5 oz grenadine (the grenadine sinks and creates the sunrise layer). Unsophisticated but pleasant. (4) Tequila Old Fashioned (Oaxaca Old Fashioned if mezcal is added) — 2 oz reposado tequila, 0.5 oz agave syrup, 2 dashes Angostura, orange peel. Add Cointreau and the Margarita variations multiply (Tommy's Margarita uses agave syrup instead of Cointreau; the Cadillac Margarita floats Grand Marnier). Reposado tequila (aged 2 to 12 months) softens the agave and works well in stirred drinks; blanco is essential for shaken citrus drinks like the Margarita.