Ensure your elderflowers are freshly picked on a sunny day for the best flavor. Avoid blossoms near busy roads. Adjust the sweetness to your liking by adding more or less sugar. When serving, dilute the cordial with still or sparkling water to taste. Garnish with a slice of lemon or a few fresh berries for an elegant touch. For a sophisticated cocktail, add a splash of elderflower cordial to gin or vodka with soda water.