Usually on the right lapel.
On the left side, always
It should be worn over his heart.
carnations
The correct way to wear a poppy is to pin it to the left collar area. If the article of clothing being worn does not have a collar, it should be worn on the left lapel area.
People traditionally wear red carnations on Mother's Day. If the carnations are red, they signify admiration. Pink ones mean gratitude and love. Also, it is traditional to wear white carnations if the mother is not alive.
wore a red carnation in his lapel for good luck
left side lapel above notch
This is more of a fashion-oriented question. When it comes to politicians, I would say no. Politicians are to wear one lapel pin: the American Flag.
On the left and closer to the lapel than any other lower order (campaign, jubilee etc) medals.
Order of Australia lapel pin. From wiki- “a gold lapel pin for daily wear is issued with each badge of the order at the time of investiture; AK/ADand AC lapel pins feature a citrine central jewel, AO and AM lapel pins have a blue enamelled centre and OAM lapel pins are plain.”
He wears a US flag lapel pin. Please note that lapel pins do not make one more or less patriotic.