I see. That is a great initiative.
My style guide is not suitable for non technical people since it requires HTML and diff understanding for the rationale, and it is too detailed. But if you think something could be extracted, that would be great.
I would recommend to just follow a style guide on the examples that you give users, or when you mention multiple possible syntaxes quickly recommending one of them, as that will determine how beginners write to a large extent.