How to enable SSHD on FreeBSD server / jail

Originally published at: https://www.cyberciti.biz/faq/how-to-enable-sshd-on-freebsd-server-jail/

I have installed FreeBSD jail and set up an IP address. However, I am unable to ssh directly into my FreeBSD jail. How do I enable OpenSSH SSHD on the FreeBSD server?