Put all ingredients, aside from the Campari and garnishes in a cocktail shaker and muddle them as best you can, releasing as much juice from them as possible.
Add the Campari to the shaker, put the lid on and shake, and strain into a glass filled with crushed ice. Top off with a splash of soda water.
Garnish with a half a cherry tomato, a pineapple wedge, a strawberry, and a basil leaf or two.