Try sparkling water (without sweetener) on the first day when the evening to help with hunger. There are no artifcial sweeteners that do not increase insulin and thereby stir up hunger.
Salt and sodium become more important for extended fasting. Measure out 1.5 teaspoons of salt in the morning and work on that throughout the day. Don’t eat it all at once … just a bit throughout the day. A pinch of salt under the tongue is one way.