Never refuse a present unless under very exceptional circumstances. However humble the giver, and however poor the gift, you should appreciate the goodwill and intention, and accept it with kindness and thanks. Never say "I fear I rob you," or "I am really ashamed to take it," &c., &c. Such deprecatory phrases imply that you think the bestower of the gift cannot spare or afford it.
Never undervalue the gift which you are yourself offering; you have no business to offer it if it is valueless. Neither say that you do not want it yourself, or that you should throw it away if it were not accepted. Such apologies would be insults if true, and mean nothing if false.
No compliment that bears insincerity on the face of it is a compliment at all.
To yawn in the presence of others, to lounge, to put your feet on a chair, to stand with your back to the fire, to take the most comfortable seat in the room, to do anything which shows indifference, selfishness, or disrespect, is unequivocally vulgar and inadmissible.
If a person of greater age or higher rank than yourself desires you to step first into a carriage, or through a door, it is more polite to bow and obey than to decline.
Compliance with, and deference to, the wishes of others is the finest breeding.
When you cannot agree with the propositions advanced in general conversation, be silent. If pressed for your opinion, give it with modesty. Never defend your own views too warmly. When you find others remain unconvinced, drop the subject, or lead to some other topic.
Never boast of your birth, your money, your grand friends, or anything that is yours. If you have travelled, do not introduce that information into your conversation at every opportunity. Any one can travel with money and leisure. The real distinction is to come home with enlarged views, improved tastes, and a mind free from prejudice.
Give a foreigner his name in full, as Monsieur de Vigny--never as _Monsieur_ only. In speaking of him, give him his title, if he has one. Foreign noblemen are addressed _viva voce_ as Monsieur. In speaking of a foreign nobleman before his face, say Monsieur le Comte, or Monsieur le Marquis. In his absence, say Monsieur le Comte de Vigny.