How do I set a reviewer for knowledge content?

You can setup a reviewer for individual pieces of knowledge (or you can do this in bulk). Your identified reviewer will get an email notifying them that content needs to be updated (on the date you select). 

In the Knowledge Base record, the 3rd tab deals with reviewers. You can setup your reviewer, a date, and frequency. 

You can also do this in bulk from the main Knowledge Base listing page. Just select the records you want to set a reviewer for. Then you'll see bulk actions available. 

Feedback and Knowledge Base