When you’re making a cocktail – whether it’s with gin or another spirit, you should keep an old bartender’s rhyme, in mind, according to Carter: sour, sweet, strong, weak.
“One part sweet, two parts sour, three parts alcohol, four parts lengthener or effervescent,” he said. “Generally you’ll create a perfectly balanced cocktail, with twice as much sourness as sweetness – something like a Tom Collins, a long refreshing drink.”
He added: “Cocktails shouldn’t be that overpowering with the alcohol, they should be perfectly balanced.”
http://www.businessinsider.com/mistakes-people-making-when-buying-ordering-and-drinking-gin-2018-4