Rim your glasses with salt (or even sugar, if you prefer).
Fill your glass with crushed ice, placing your lime popsicle right inside the glass (upside down of course!)
Pour tequila, water and club soda into glass, right over the popsicle.
Optional: garnish with a slice of lime.
Notes
The combination of tequila, water and club soda is to taste. You can add more club soda to your preference, depending on how you like your tequila ratio!