To Beard or Not to Beard, That is The Question

[Esaias]

What are the guidelines for pastors or church elderships establishing extra-Biblical rules and regulations that all believers in that assembly are expected to accept and obey?

I mean, surely there are some guidelines, rules, or SOMETHING that would provide some guidance to pastors and churches to help them navigate these waters?

And, how are Christians to recognise the difference between an extraBiblical pastoral church regulation that God backs up vs an extraBiblical rule or directive that God does NOT support? I mean, how does a Christian judge the difference between a pastoral standard and a popish presumption?