Rim the glass. Pour the salt onto a small plate. Rub the lime wedge around the edge of a pint glass. Dip the rim of the glass into the salt. Set aside.

Shake. Fill a cocktail shaker halfway full with crushed ice. Add tequila, lime juice, and grapefruit juice. Shake until cocktail shaker is beaded with water, about 15 seconds.

Serve. Pour cocktail into prepared pint glass, top with Squirt, and stir. Garnish with the lime wedge and enjoy! If you want you can also garnish with thin strands of lime zest by running a citrus zester along the outside of a lime.