How to Install Disqus for Comments on Tumblrby Andrea Ruiz
While Tumblr has many flexible features for bloggers, its blogging platform lacks a native commenting feature. You can enable replies to your posts from other Tumblr users who have followed your blog for more than two weeks, but there is no built-in way for non-Tumblr users to comment at all. Disqus bridges that gap by providing a commenting script that works seamlessly with virtually all native Tumblr themes; you can quickly enable Disqus comments through your blog's settings.
Visit the Disqus home page and click the "Add Disqus to Your Site" button. Follow the onscreen instructions to register a Disqus account, then click the confirmation link you receive in the email address you entered.
Log in to your new Disqus account and click the "+Add" button on your dashboard. Create a site profile for your Tumblr blog by entering a name, and then selecting a desired shortname and category for your blog.
Click the "Finish Registration" button to complete your blog's Disqus site profile, and then click the Tumblr icon. Copy the shortname displayed to your computer's clipboard.
Log in to your Tumblr account in a separate browser tab, and visit your customization page by clicking the gear icon.
Select the blog to which you'd like to add comments, then click the "Customize" button.
Scroll down the customization settings and enter your Disqus shortname in the "Disqus Shortname" field.
Click the "Save" button, then click the "Exit" button.
Return to the browser tab with your Disqus installation instructions still open and click the blue "Verify" button to verify that you've correctly installed Disqus comments on your Tumblr blog.