You will probably also want to begin at once doing some shopping, even before you go looking for special souvenirs. Shopping in Paris will give you an idea of the vitality of the city, whether you are buying food or any other article. It is a large city where the people work hard.
Shops selling food are open from 8.30 a.m. ( the bakeries from 7 ) to 1 p.m. and from 4 p.m. to 7.30 p.m. Other shops ( fashion boutiques, bookshops, hairdressers, etc. ) are mostly open from 9 a.m. to 7 p.m. without interruption. Food shops are also open on Sunday morning, but on Monday most of them are closed ( some only in the morning ).
Remember that in many shops ( fashion shops, those selling perfume, jewelry, or other luxury goods ), if you show your passport and a special card issued by your bank or by American Express, you can make a saving on sales tax. There is no embarkation tax at the Paris airports.