Choose a gin first. Taste the gin by itself before mixing with tonic. The type of gin you choose will determine your gin and tonic's defining characteristics. Do you prefer an herbal drink or a dry drink? Do you want to tone down the quinine or enhance it? Botanical gins, which are made with a combination of spices and herbs that bring out floral flavors will make for a different G&T than a dry gin, which is juniper- and grain-forward.
Then choose a tonic. The quality of tonic water is crucial to creating a dynamic G&T. “If you can't use a good tonic, don't bother making the drink,” Figueredo says. Mass produced, store bought tonic waters contain fake sugars and chemicals, while small batch brands like Fentimans, Fever-Tree and Q Tonic taste better and are made with natural sweeteners like agave nectar. Choose tonic based on the qualities in the gin and counter them for balance, such as pairing a sweet or lighter tonic with dry gin.
Deconstruct the gin for garnish. Adding floating garnishes to the cocktail not only makes for good presentation, but also aromatics that gently arouse the nose before taking a sip. If the gin is distilled with coriander and cardamom, use a couple of coriander seeds and cardamom pods in the glass with the traditional G&T citrus peel. But don't overdo it: most of the drink's appeal is in its simplicity.