I eat my peas with honey. I've done it all my life.

I know that the word "etiquette" originally meant (and in French still does mean) "pasted-on label." What no dictionary seems able to tell me is why and how the word made this leap of meaning. I like to imagine the Sun King, shocked by the manners of the average French aristo, ordering signs to be pasted up on the walls of Versailles reading "Do Not Spit on the Throne-Room Floor," "Let Archbishops Through Doors First," and the like. I don't suppose I'm right, but am I even close?
Very close, as a matter of fact. The meaning of the French etiquette is, as said, "ticket, note or label," especially the sort of label or sign that is pasted to something, and the French "etiquette" is, in fact, the source of our English "ticket." In English, of course, we use etiquette to mean the rules of behavior observed in polite society. Proper etiquette comes in a variety of flavors, from simple personal manners (don't sneeze on the wedding cake) to the writing of thank-you notes (don't hold your breath) to the suspiciously convenient codes of professional etiquette that frown on doctors or lawyers criticizing their colleagues. Bits of etiquette, once learned, can be hard to forget. An incorrectly set dinner table, for instance, drives me absolutely bonkers!
The connection between "a ticket or note" and "the proper way of behaving" senses of "etiquette" came prior to the 18th century, when the rules and ceremonies of a court were sufficiently complicated that newcomers and visitors were often issued a list of "dos and don'ts" printed on a small card. By the time "etiquette" was imported into English around the 18th century, its meaning had broadened into our modern sense of "how to behave properly in a given situation."
You see!