This is quite easy, just add this to your PHP file:
error_reporting("E_ALL") ;
you can also achieve this via .htaccess if AllowOverride is set correctly:
php_flag display_errors offIf you would like the errors to be logged to a file though, you can also do that:
php_flag log_errors On php_value error_log /var/log/apache2/site.errors.log