Make advice an invitation
Ask whether someone wants suggestions. Some players enjoy thinking aloud; others want space to reach their own decision. Neither preference requires a justification.
Explain reasoning without a verdict
Describe what you noticed and what you expected it to change. Avoid using a score or a single mistake as a judgement of another person.
Keep learning reciprocal
An experienced player may know the rules well while a new player notices a different possibility. Let questions move in both directions.
Pause when the discussion stops helping
A post-game conversation can become tiring or uncomfortable. Offer a break or a change of topic without insisting that every decision be resolved.
Respect the actual group
Reading, hearing, reaching and concentrating can vary from person to person. Ask what practical arrangement helps rather than assuming one way of playing suits everyone.