To make liquid float is done by carefully pouring a small amount of liquid that balances as the top layer of a drink.Use the back of a barspoon to gently disperse the ingredient on top of the ingredients already in the glass. This technique is often used to to make layered shots and works best when you mix heavier and lighter liquor. The heavier, of course, sinks while the lighter rises. To maintain the layering effect the drink should not be stirred. Practice is the best way to get the feel for creating clean layers, so start now and soon you will become a true cocktail magician.