Fill a cocktail shaker with ice. Add the pineapple juice, tequila, and lime juice. Shake until chilled.
Strain into a glass filled with ice. Garnish with a wedge of pineapple or a slice of lime.
Enjoy immediately.
Notes
If you like a sugar or salt rim, fill a small dish with water and another small dish with the sugar/salt. Dip the edge of the glass in the water and then into the sugar/salt. Set aside until ready to use.