Disqus

See Steegle's How to Install Disqus Instructions with video

1. Sign up at https://disqus.com/profile/signup/intent/

2. After creating your Disqus account get the Universal Embed Code.

3. https://help.disqus.com/customer/en/portal/articles/472097-universal-embed-code

4. You have to remove the commenting from the sections highlighted

5. Here's the code from my site: