Maurice,
Right now, the best way to do that is by adding the JFBCLike and JFBCComment modules to your K2 pages. For the 4.0 release, due out at the end of this month, we'll be adding K2 integration similar to the Joomla article/content integration we already have for automatically adding the Like's and Comments.
Hope that helps get you started, and hopefully, soon, we'll have a much smoother experience when integrating with K2.
Alex
K2 and Facebook "like" and comments
