As far as I know, this isn't something that's ever really been talked about. We've got a potentially extremely useful resource on Puzzling Meta: the faq tag. But I'm not sure how we should use it. Documenting tips, information, puzzle requirements, what-to-do/what-not-to-do questions, etc. could potentially all belong here. Tools and resources we want in a shared way that may not be as suited for being on-site resources. Site policy, important past discussions, etc.
It's a broad topic, but it's, again, potentially extremely valuable as a resource. I've asked a Meta SE question about how the Meta FAQ should be used, but ultimately, it's up to you all.
(How) should we set up and use this resource?