I don't know about guides, but I do agree it can be a little confusing. Trying to work out what instances are and which one you should join is difficult until you understand the concept and a little about how the tech works - it's the same with the threadiverse. Realising it's like email domains is what made it click for me.
And if you personally ever decide to get into Mastodon: you're on kbin already, which federates with Mastodon and has support for microblogging, so you don't even need to do anything new - you just need to start using that functionality on kbin!