Talk in terms of the other person's interests.
There is no such thing as constructive criticism.
Patience and perserverance will accomplish more in this world than a brilliant dash. Remember that when something goes wrong.
Forget yourself by becoming interested in others. Do every day a good deed that will put a smile of joy on someone's face.
Make the other person feel important - and do it sincerely.
Don't ask a man what is important to him. Watch how he spends his time