Many blogs offer the opportunity to comment on blog posts within the blog site itself. However, I think it's better to use Twitter for this.
Blog comments are only visible on the blog itself, so you only see them when reading the blog post. With Twitter, the discussion on your blog post becomes public, everyone can see it and join the discussion. And a nice side effect is that it also is a way to promote the blog post to a greater audience.
Furthermore, depending on the platform you use for your blog it might even mean you have to build (or integrate) commenting yourself or use an existing service. Then you might have to deal with preventing spam and inappropriate comments. And you also have yet another place to check for comments, while you're already busy checking Twitter and other social media.
So why not use Twitter for this? My workflow for using Twitter as my promotion and commenting platform is as follows:
Step 1 - Write and share your blog post
First, I write a blog post (duh). Then, I share that post to Twitter. You can do this by hand by typing a tweet, but better is to add a "Share on Twitter" link to your blog post:
This link creates a window with a new tweet that is pre-populated with a text, the URL to your blog and your Twitter handle, i.e. the author of the blog.
Note that all CAPITALIZED_PLACEHOLDERS in the URL need to be replaced by your specific text, URL, name etc.
To share your blog post, you press the link yourself, and voila, a tweet is posted so you let the world know you wrote another awesome blog post.
And the nice thing is that everyone else who is reading your blog post can also click that same link and promote your blog post too! 💯
Step 2 - Comment on your blog via Twitter
Now that your blog post is live you want readers to be able to comment on it and start a lively discussion. Let's use Twitter for that, because it's something Twitter is good at.
Navigate to the following URL, which is a search query on Twitter for the URL of your blog post:
And you'll see the tweet you've just posted in step 1.
Now add this link to your blog post too and name it "Discuss on Twitter". When someone clicks the link and replies to one of the tweets in the search result, that reply will also appear in that search result and this way your are building a discussion thread on your blog post.