This is ambi-epistolary – hey-ho, there’s a nonce-word for the ages! Yes, ambi-epistolary, it can be made with equal facility out of letter paper of either persuasion, A4 or American 8½ ×11″. How’s that for thinking globally?
You make two pieces and one fits into the other. Or the other way around. The male becomes female, the female becomes male…oh, it’s the Rocky Horror Picture Show all over again. This is one reason Republicans won’t read this blog.
I have a cube model of this, too.
Enough blather – the directions are right here.