Cucumber and Elderflower Gin Martini

Name: Cucumber and Elderflower Gin Martini
Ingredients: 3 oz Tanqueray London Dry Gin; 3⁄4 oz Elderflower liqueur; 1⁄2 oz Lemon juice; 1⁄2 oz Sugar syrup 'simple'; 4 slice Cucumber; 2 leaf Basil leaves