Click on the members screen name, then click the bell to the right of their name and you will get a pop up menu with follow options. Click submit and you are a follower. To unfollow, do the same then uncheck the "follow (member's name)" and click submit and you will unfollow that member.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .