I followed instructions at

http://ikiwiki.info/plugins/po/

and added to configfile

    po_master_language => 'en|English',
po_slave_languages => [ 'zh|Chinese' ],
    po_translatable_pages => '(* and !*/Discussion and !blog/*/comment_*)',
    po_link_to => 'current'

and did

  ikiwiki --setup configfile

But I don't seem to see any change in the newly built site.

How do I actually use po to create translation pages?

1) I have existing pages that's in English. How do I add translated versions of some of those pages in the slave language?

2) How do I add new pages with the primary language version and alternative versions in slave languages?

The documentation of po is not explicit with what are the concrete steps.