Start with one complete reference
Share the page or rules sheet with everyone. Write its title and any agreed changes on a separate note. An isolated scoring screenshot rarely explains the whole game.
Ask specific questions
Which pack is used? What happens after everyone passes? When can someone declare a lone hand? Which scores and target apply? Record the answers without mixing a preferred answer from each of several sources.
Make the agreement visible
Keep the note near the scorekeeper. If the group changes a setting, decide when the change takes effect before another hand begins. Do not apply an unannounced change retroactively to an earlier result.
For apps
Record the visible mode and setting labels. An unknown option should remain a question until the provider’s help or a concrete test resolves it.