[NTG-context] How do I write a digital book that can become a physical book without a lot of modifications?

[amano.kenji]

A digital book doesn't need to be double-sided.

But, a physical book can be double-sided.

Double-sidedness may require adjusting contents in many places.

How can I write a digital book that doesn't have to be heavily modified in order to become a physical book? I want almost no modification at all.