Slice the store-bought angel food cake horizontally in thirds. Place one layer of angel food cake on the bottom of the trifle bowl. Then layer with three-quarters of the cool whip, and all but 1/2 cup of the chopped strawberries.
Place another layer of angel food cake on top of the fresh strawberries. Followed by three-quarters of the cool whip. Smooth with a spatula, then place all but 1/2 cup of the blueberries in the trifle.
Lastly, place the last layer of angel food cake and the remaining cool whip. Spread so that the cool whip just covers the angel food cake. Layer another ring of strawberries around the top and blueberries in the middle. Refrigerate for at least a half hour. Enjoy within 2 hours of making the trifle.