Create keys for SSH (in this case on linux command-line) ssh-keygen -t rsa
Name server hostname (I used these instructions (archive) for hostname)
Set reverse DNS in VPS server console equal to FQDN
Change SSH port & disable password authentication with sudo nano "/etc/ssh/sshd_config" then restart ssh sudo systemctl restart ssh
create non root user, copy .ssh folder from root to their profile, making sure to chown newuser for the authorized_keys file, and add the user to group sudo – sudo addgroup groupname.
Add auto security updates. sudo apt-get install unattended-upgrades
sudo dpkg-reconfigure unattended-upgrades
sudo nano /etc/apt/apt.conf.d/50unattended-upgrades **requires root email for notifications*