First-time travelers to France might be surprised to be greeted by two kisses on their cheeks, even from relative strangers. In Paris, you will receive four kisses instead of the customary two that the rest of the country uses. Expect cheek kisses when you greet somebody and when you say goodbye. Both men and women greet with kisses equally. Greetings and leave-takings are thus rather time consuming. However, anything less would be rude.
As you shop in France, greet the store-keeper with "bonjour" which is the equivalent to "good day" in English. Upon leaving the store, "Merci" (thank you) suffices. Learn a least a couple of key phrases in French before traveling, because any attempt to speak French is highly appreciated both from store-keepers and waiters. Start off with the French you do speak, and you will be awarded with attempts in English back. However, it is considered highly impolite to launch into English without at least trying to speak some French. You will likely be met with blank stares and some degree of annoyance, unless you specifically read a sign on the store that indicated that English was spoken.
France and the United States have differing perspectives on time. You will rarely see a French person multitasking beyond walking down the street and talking on the cell phone. Taking your time is important to the French, and anything worth doing should be done well. They see no merit in rushing through a task, but rather appreciate presentation and quality. Don't allow the lines in the store upset you as the cashier beautifully wraps a small purchase. Even your bread and pastries will be handed over to you in attractive packages. Etiquette dictates that you let other customers take their time in France, and they will grant you the same courtesy.
The same rule of thumb applies in restaurants. Waiters will not hover over you but will allow you and your table companions to remain at the table for as long as you wish. Tourists wishing to cram in as much sightseeing as they can in a day might be frustrated by what they perceive as slow or bad service, but look at it as the French do. You have time to enjoy your meal, dining companions and conversation.
There is one last etiquette tip to keep in mind. In the United States, it is perfectly acceptable to run to the store in your workout clothes or go to the curb to pick up your newspaper in your pajamas. In France, you would be considered eccentric to be on the street in your workout clothes, unless you were on your way to or from the gym. You will see that the French dress casually during their free time, but the clothes do tend to be more tailored and slightly more formal than most Americans are used to wearing. For example, when was the last time you ironed your polo shirt or jeans? So for etiquette's sake, pack clothes that can be dressed up or down, but that are not too casual.