Manual partitioning with encrypted /home

Default Manjaro installation scheme has only one partition.

I will like to put my /home on a separate encrypted partition.

I am installing Manjaro on a new hard disk so everything is empty currently.

What partitioning scheme is needed/ prescribed/ recommended so that I can install additional OSes if needed?

You can amend this guide to achieve your desired result - instead of creating a partition for /boot - you create a 30G partition for root - and a partition for your home - mounted at /home - then tick the encryptionbox for your home partition.