WordPress.org

1. Once activated, go to Google Subscribed Links, and click on the Create a Subscribed Link button.
2. Choose Submit the URL of a feed file.
3. Fill in the form (don't tick "Only read DataObjects"); for the URL write your normal feed URL but add a coop=1 query to the end of it. For example, http://example.com/feed/?coop=1 or without fancy permalinks http://example.com/?feed=rss2&coop=1.

Once you've submitted your feed, you can then spread the word and get people to subscribe!