On the day before the competition, make sure you eat an easily digestible, carbohydrate-rich diet. Avoid fatty and high-fiber foods! The longer the load duration, the more crucial are full glycogen stores and a balanced fluid and electrolyte balance.
In the pre-competition hours, make sure you have a regular intake of fluids and energy from carbohydrates. However, there should be no feeling of fullness. The last main meal is about 3-4 hours before the assignment.