So I’ve already noticed today that you have to go thru some extra steps to make comments work on a Tumblr blog. If you didn’t choose Tumblr, ignore this post! But if you did, please follow the steps involved to 1) register your blog on Disqus and 2) enable comments on your Tumblr blog.
Read this first: http://www.tumblr.com/docs/faqs#comments
Make sure you’ve selected a theme that allows Disqus. (Disqus = discuss, get it? :) )
Sign up for Disqus here: http://disqus.com/comments/register
I have created a screencast so you can see how it works. Sorry I did not anticipate that as an extra step! We are ALL learning this week ;)