Whip the cream:
Whip the cream and sugar together until stiff.
Assemble the cake!
(I experimented with my layering technique: custard alone between the first and second layers, strawberries alone between the second and third layers, and strawberries and custard between the third an fourth layers. In the future, I'll put strawberries and custard between every layer.)
Place one cake layer on a wax paper-lined baking sheet. Brush the top of the layer with 1/3 of the reserved strawberry juice. Cover with a layer of strawberries, and then with a layer of custard. Top with the next layer of the cake, and repeat: strawberry juice, strawberries, custard, cake layer. And again.
Using a spatula, cover the entire cake with whipped cream. Top with either leftover macerated strawberries, or a few "raw" strawberries. (Next time, I'll go with the latter.)
Chill the cake for at least 8 hours before serving, so that the cake has time to absorb the strawberry juices. Bring to cool room temperature before serving.
(To transfer the cake from the baking sheet to a cake stand, use the wax paper to gently scooch the cake from one surface to the other, then tear away the visible wax paper.)