The concept of 'leftover wine' is common on social media, but not in real life. How to make a crystal clear cube: Start with distilled water, then boil and cool twice to remove excess oxygen, then freeze. Fill the cavity of an ice tray with berries, fresh herbs, fruit slices or edible flowers, then freeze them and use them in a compatible cocktail. Using custom ice cubes is a great way to enhance your visual appeal. The taste of a cocktail is most important, but so is its appearance. To enhance your cocktail experience, add flavors like spices, herbs, fruits and even vegetables to the water. Simply boil a cup of water and sugar separately, then pour into a clean bottle or jar and refrigerate until needed. Instead, bartenders use a liquid sweetener called simple syrup. The sweetener of choice is not sugar, because even the best sugar dissolves slowly in a cocktail shaker. Jams, jellies and preserves bring sweetness, flavor and color to cocktail creations. Balanced cocktails have enough sweetness to balance the sour and astringent ingredients, and that sweetness doesn't have to come from juice or simple syrups.