How do you PM someone?

I posted this in the wrong place earlier but the title says it all. I cannot find the 'send message' or whatever button it is. Any ideas?

 

Click on their picture... Select start a conversation

 

At the top right of your screen click on your user name. This gives you access to a whole host of things you can do.

The system doesnt show the words Private Messages or PM the new word is "Conversations"

Click on conversations. This will bring up old messages too.

Then Click on "start a new conversation"

I hope that helps