Greet with smile
Begn with friendly behaviour
Refrain from direct critisism, complaint
Avoid argument - no one wins
Praise & appreciate honestly
Praise on small improvements/achievements
Build a good reputation on other person
Admit own mistake honestly
Callout others mistake indirectly
Generic statement not pointing to one
Let other person save face
Make the mistake appears easy to correct
Sincerely make other person feel important
Know person by name
Listen others - encourage other person to open up
Understand other person's interest & align yourself
Respect others opinion - be empathetic
Express the noble motive behind the job
Motivate others by opening up challenges
Ask question to produce ideas - refrain from giving orders
Let the other person perceive/produce/extend the idea/thought to own the job