In a tall glass, preferably a pint glass, pour in the tequila. Follow this up with half an ounce of freshly squeezed lime juice and a pinch of salt to balance the citrus notes.
Fill the glass up to the halfway mark with grapefruit soda. The grapefruit soda complements the tanginess of the lime while adding a slight sweetness and a bit of effervescence for a well-rounded flavor.
Finally, top off your glass with the light beer and garnish with a grapefruit wedge.