So you wanna work on the Riak docs, eh? Good choice. You'll have a lot of fun and learn some very cool stuff. The documentation below will help you contribute.

• Information currency --- Wrong information adversely affects both enterprise and open-source users. You should prioritize this above all. This means paying close attention to versioning, i.e. making sure that information always ends up reflecting the version in play.
• Clarity and concision --- It doesn't have to be poetic. Always strive for concision and clarity above all else in your wording. Assume that the reader is there for a specific purpose and wants to get in and out as quickly as possible. There are exceptions to this, however. The theory and concepts docs do provide you a bit more space for wordsmithery because readers' expectations and goals are somewhat different. But even there, less tends to be more.
• Completeness --- The Basho docs are never complete. New versions and features come along, old info turns out to be misleading or downright wrong, etc. Nonetheless, you should leave as few blind corners as possible. When a new feature comes along (and there will be quite a few in 2015), make sure that you've used the feature in a personal project of some sort, that all of its capabilities, limitations, caveats, etc. are well covered.

A few more links that will help get you up to speed and contributing:

• Getting Started
• Anatomy of the Docs
• Markdown Crash Course & Standards
• What Should I Contribute?