private messaging
 

I am trying to private message.

I click on the user's username, I get a menu of 3 or 4 options, the 2nd of which is private message.

I click that and I get their profile page.

I'm using a windows 8 machine with Chrome.

What can I do to PM?

From the profile there's a send pm on the left side

Yes, from their profile page there is a link on the left to send them a private message. It produces a pop-up window, so if you have a pop-up blocker you may need to hold Ctrl or Alt while you do it.