Line the bottom of a 12x8" baking dish with 8 slices of the pound or golden loaf cake. Top with the 1 cup strawberries and 1 cup blueberries, spread berries to cover cake completely. Then add thawed Cool Whip and spread topping over berries until berries are covered.
Design "Stars and Strips" with 48 strawberry halves and 54 blueberries - Blueberries are 9 berries long at 6 rows high. Strawberries are 3 rows of 6 and 3 rows of 10.