— Aaron Davis 🏘️ (@mrkrndvs) September 17, 2017
Aaron, there are a couple of different ways to set up IndieWeb replies in WordPress (or even on other platforms like Known).
Known has a simple reply mechanism, but isn’t always good at including the original context for the reply making the individual post as stand-alone as one might like. Known includes the URL of the post it’s a reply to, but that’s about it. It’s contingent upon the user reading the reply clicking on the link to the original post to put the two together. This is pretty simple and easy when using it to reply to posts on Twitter, but isn’t always as flexible in other contexts.
One of the added values of replies in WordPress is that there’s a bit more flexibility for including a reply context to the post. You’ll note that this reply has some context at the top indicating exactly to what it is I’m replying.
The first way to generically set up a reply on almost any platform that supports sending Webmentions is to write your reply and and include some simple semantic HTML along with the URL of the post you’re replying to that includes a class “u-in-reply-to” within the anchor tag like so:
<a class="u-in-reply-to" href="http://example.com/note123">The post you're replying to</a>
<div class="p-name p-content"> Good point! Now what is the next thing we should do?</div>
Some of this with additional information is detailed in the reply page on the IndieWeb wiki.
If you’re using WordPress, you can do this manually in the traditional content block, though you likely won’t need the div with h-entry as your theme more likely than not already includes it.
More automated replies
If you’d like a quicker method for WordPress, you can use a few simple plugins to get replies working. Generally I recommend David Shanske’s excellent and robust Post Kinds Plugin which handles both reply contexts as well as all of the required markup indicated in the manual example above. Naturally, you’ll also want to have the Webmention Plugin for WordPress installed as well so that the reply is sent via Webmention to the original post so that it can display your reply (if it chooses to–many people moderate their replies, while others simply collect them but don’t display them.)
A few weeks ago I wrote about configuring and using the Post Kinds Plugin in great detail. You should be able to follow the example there, but just choose the “reply” kind instead of the “read” example I’ve used. In the end, it will look a lot like this particular reply you’re reading right now, though in this case, I’ve manually included your original tweet in the body of my reply. A more native Post Kinds generated reply to a tweet can be seen at this example: http://boffosocko.com/2016/08/17/why-norbert-weiner/
Naturally, your next question may be how to POSSE your replies to other services like Twitter. For that, there’s a handful of methods/plugins, though often I suggest doing things manually a few times to familiarize yourself with the process of what’s happening. Then you can experiment around with one or more of the methods/plugins. In general the easier the plugin is to set up (example: JetPack), the less control you have over how it looks while the more complicated it is (example: SNAP), the more control you have over how the output looks.
If you’d like, feel free to experiment sending replies back to this post while you try things out. If you need additional help, do join one or more of us in the IndieWeb chat.