Welcome to Sup! Here's how to actually use it.

To get started, just run 'sup'. Assuming this is your first time,
you'll be confronted with a mostly blank screen, and a little message
at the bottom telling you that you have no messages. That's because
Sup doesn't have any messages in its index. In order to add messages,
Sup needs to have some "sources" from which to load messages.

If you want to play around a little at this point, you can press 'b'
to cycle between buffers and 'x' to kill a buffer. There's probably
not too much interesting there, but there's a log buffer with some
cryptic messages. You can also press '?' at any point to get a list of
keyboard commands, but in the absense of any email, these will be
pretty useless. When you're done, press 'q' to quit.

Now let's add a source to Sup. Run sup-import with a URI pointing to
an email source. The URI should be of the form:
- mbox://path/to/a/filename, for an mbox file on disk. (You can also
  just provide the filename).
- imap://imap.server/folder or imaps://secure.imap.server/folder for
  an IMAP server.
- mbox+ssh://remote.machine/path/to/a/filename for a remote mbox file.

Note: sup-import tries to be smart about setting the labels on
      messages that it adds (including the special labels "unread" and
      "inbox"). There are options that control this behavior, and it's
      worth taking a look at the output of sup-import --help to make
      sure that you don't end up with 1000 new messages that you've
      actually already read.

If sup-import requires a username and password for the source, it will
prompt you for one. Either way, it will start loading messages from
that source into the index. Depending on the size of the source, this
may take some time. Don't worry! This is a one-time step, and all the
computation done now makes operating on the index faster.

Now, before we run 'sup' again, take a moment to edit your
~/.sup/config.yaml file. Replace "Your Name Here" with your name,
"your.email.here@domain.tld" with your email address, and fill in your
.signature file if you choose. You can also set the default editor.

Now run 'sup'. You should messages being loaded into your "inbox!"
There are two things that are worth understanding at this point.
First, Sup does not actually use folders. Instead, messages can have
any number of labels applied to them. Rather than viewing a folder,
you view the results of a search. So your inbox is simply the set of
messages that have the 'inbox' label applied to them.

Second, Sup groups together messages into threads. You rarely operate
on an individual message in Sup.

Press enter to view a thread. 

To be continued...