How do I PM somebody???
Click on their name and that will take you to their page. Then click on "start conversation" in the box to the right. If it doesn't say "start conversation" then they have limited the conversations they get to just friends. So you will have to make a friend request. There will be a message box, but don't waste your time on that until you have been accepted as a friend.
I didn't have a "start conversation" in my box as I didn't know how to allow that. So I changed my settings, but I may have not done it correctly. I should check.
When you are on your home page, you can click on "friends" and you can then receive friend requests, check your list of friends, etc.