Do not call someone more than twice in a row. If they don't answer the phone, assume they have an important matter to attend to.

Return borrowed money before the person who borrowed it remembers or requests it. It demonstrates your honesty and character. The same is true for umbrellas, pencils, and lunch packs.

Never choose the most costly dish on the menu while someone else is paying for your lunch or supper.

Don't ask embarrassing inquiries like, "Oh, you're not married yet?" 'Don't you have any children?' or 'Why didn't you purchase a house?' Why not purchase a vehicle instead? It's not your problem, for God's sake.

Always leave the door open for the person behind you. It makes no difference if the person is male or female, senior or junior. You don't get smaller by being kind to people in public.

If you share a taxi with a buddy and he or she pays now, try paying the next time.

Be respectful of diverse points of view. Remember that what appears to you as a 6 will look as a 9 to someone facing you. Furthermore, a second view is useful as an alternative;

Never, ever interrupt someone who is speaking. Let them pour it out. As the saying goes, "hear them all and filter them all."

If you tease someone and they don't appear to like it, stop and don't do it again. It motivates you to achieve more and demonstrates your gratitude;

When someone assists you, say "thank you."

Give public appreciation. Privately criticize;

There is virtually never a cause to make a weight comment. Simply state, "You look wonderful." They will talk about reducing weight if they want to;

Don't swipe left or right when someone shows you a photo on their phone. You never know what's going to happen next;

If a coworker tells you they have a doctor's appointment, don't question what it is for; instead, simply respond, "I hope you're alright." Put them in the awkward situation of having to inform you about their personal ailment. If they want you to know, they'll tell you without your asking.

Treat the cleaner with the same regard as you would the CEO. Nobody is impressed by how disrespectful you can be to someone in your position, but people will notice if you treat them with respect.

It is impolite to look at your phone while someone is speaking directly to you.

Never provide advise until requested;

If you encounter someone after a long period, don't ask them their age unless they want to talk about it.

Mind your own business until it directly concerns you - simply keep out of it;

If you're chatting to someone on the street, take off your sunglasses. It is a gesture of deference. More importantly, eye contact is as crucial as your words.

Never boast about your wealth in the presence of the impoverished. Similarly, don't bring up your children when you're infertile.

Try to say "Thank you for the message" after reading a hopeful message.