How do I comment/reply to a post in Commons?
Go to the Commons tool.
Select the Commons tool from the Tool Menu of your site.
The Commons page will display.
The most recent posts will appear at the top of the screen.
Click the Reply link.
Click the Reply link just below the post to respond to that post.
Type your response and then click Post Comment.
View reply.
Your reply comment will appear indented just below the original message.