You can also add external hyperlinks and bold text to highlight the important points of your comment policy.
To add your comment policy, open the Blogger dashboard and goto Settings -> Comments. Type your HTML text in the box that says "Comment Form Message". Save Settings.
When a visitor opens your comment page, he will see this policy just above the comment textarea.
The comment policy of this site says: "Comments posted on Digital Inspiration are moderated and will be approved only if they are on-topic and not abusive. Avoid including website URLs in your comments"