Refrigerating Chocolate Mousse Layer Cake?

I am making a Chocolate Mousse Layer Cake,(thank you Paula Deen), for a presentation on Monday. I definately want the cake to be edible and as fresh as possible but I am not sure if I should keep the cake refrigerated? I feel so stupid asking this question because I am sure I should refrigerate it. I will probably be making the cake tomorrow, 6/28, but if I can, I will wait until Sunday. I would make it Monday morning but I have another cl before the time I need the cake. Any suggestions? I'll accept advice from anyone, but I would prefer it if you actually knew what you were talking about.