The source combines strongly brewed chilled coffee with sparkling water and ice, using Topo Chico as one example. Its extracted recipe lists equal four-ounce portions of coffee and carbonated water before ice. The reviewer prefers unflavored water so that a competing fruit flavor does not dominate the coffee, while noting that preference is individual.
The important preparation decision is concentration. Sparkling water adds dilution immediately and the ice adds more as it melts, so an ordinary-strength coffee may not give the balance you expect. Use a clearly recorded concentrate or flash-brewed coffee and account for every part of the final liquid. Pour gently into a suitable glass with headspace for foaming.
Start without syrup or extra flavors, then adjust one ingredient at a time. Compare coffee strength before changing beans, since dilution alone can explain a weak result. Cold brew and hot-brewed iced coffee are different starting preparations, so note which you use. This guide interprets the source's recipe without claiming a new BeanScene tasting or requiring one bottled-water brand to make the drink work.

The conversation
A good question can make a better brew.