Once WordPress is up and running…

I was getting an error:

Which, for all the world looks like a file-permissions-y thing

th cd go into your wordpress installation folder and then:
sudo touch .htaccess
sudo chown -v :www-data .htaccess
sudo chmod -v 664 .htaccess
sudo sed -i "s/AllowOverride None/AllowOverride All/g" /etc/apache2/apache2.conf
sudo a2enmod rewrite
sudo service apache2 restart

Now go to WpAdmin -> Settings -> Permalinks. Choose permalink structure and hit “Save Changes”. Now .htaccess should be populated with wordpress rewrite rules and conditions.