sudo apt-get update
sudo apt-get install phpmyadmin
You'll get asked which system you want to install phpMyAdmin on. Nginx is not an option, so hit tab & enter to skip this.
Next you'll be asked if you want dbconfig-common to configure a database.
Create a symbolic link from the phpMyAdmin application to the public folder.
sudo ln -s /usr/share/phpmyadmin /var/www/html
Enable the mcrypt PHP module.
sudo phpenmod mcrypt
sudo systemctl restart php7.0-fpm
phpMyAdmin is now set up at your domain or IP (ex: example.com/phpmyadmin)
ToADD: create symbolic link for security (obsure /phpmyadmin from public)