Ensure sugar cookies are completely chilled before applying the icing to prevent it from melting. For best results, refrigerate cookies after baking until they are firm and cold. When decorating, prepare bowls of various icing colors and sprinkles to streamline the process. Any crust forming on unused icing can be easily remedied by stirring. Allow up to 24 hours for the icing to set completely before stacking. Avoid excess extract, which can overpower the cookie’s flavor—1/4 teaspoon is sufficient. Use squeeze bottles or a finely snipped piping bag for precise application; squeeze bottles tend to offer greater control.