A question for supplement creation

[FateAce]

I'm getting ready to create a campaign world to use as a base for more sandbox campaigns (much like pathfinders Inner Sea setting, or even the old Mystara setting). I just have one major question.

When writing my document, should I structure it as an adventure using the adventure template, or should I structure it similar to the core rulebook since it's not technically an adventure? I'm probably not even going to have ANY predefined adventures in it, and just keep them in a separate download, but what do you think?

[Solomoriah]

There's no standard for the layout of this kind of book, since we don't officially publish any of them. Were I to do so, I'd probably use the adventure template to start with.

[mTeasdale]

For all the supplement I have written, I have used another supplement and changed the content.