Getting Started with Daily Kos: Some Key References for Writing, Formatting, and Recommending Posts and Comments

Here's a set of short video tutorials:
DK5 Tutorial: Writing a diary, embedding images, navigating comments

Here's a text-and-image version of the tutorial:
DK5 How-To: Writing, Editing, Publishing a Diary

The next two resources explain some finer points about images and embeds.
First, Krotor on working around sizing constraints on images:
Step-by-step guide: How to include maps, charts, and other detailed images in your Daily Kos diaries

Second, Mokurai on working with embeds:
What Can You Embed?

The following resource by TrueBlueMajority explains the recommendation process at Daily Kos, describing not only why recommending posts and comments matters but also how to do it.

You may also appreciate the following two references on site policies:
Rules of the Road provides a concise reference for new and experienced site users regarding the DOs and DO NOTs at Daily Kos.

Community Guidelines is the most recent diary covering moderation rules and what sort of content is and is not acceptable at Daily Kos.

The next three posts offer more how-to suggestions:
What's new at Daily Kos 4 Note that DK5 has partly superseded DK4, but not entirely. Many of the "old-style" (Perl) pages that were innovations for DK4 are still in service, so this post offers some basic tips about those sections of the site.

Cranky Users Feature Roundup

New Diarists: Resources for all has lots of links to various tutorials created by Kossacks, for Kossacks to help you get started. Many topics are covered.

The two resources below, written by experienced and popular site posters, offer excellent suggestions for preparing a post that attracts positive attention and participation.
Writing Successfully at Daily Kos

How NOT to write a Daily Kos Diary