Travelling to France and Italy, Packing Advice and Tips?

[wingedd.]

This is my first time in Europe so I need some advice! I'm travelling to France and Italy in a little more than a week and I need some tips and advice on what to pack. I'm in France/Italy for two weeks and will be travelling a great deal.

Example questions...
Number of pants, shirts, socks, etc....
Essentials for Parisian/Italian fashion, what's in?
Do I need to bring some formal wear?
Do I need a travel-sized umbrella?
Do French/Italian town stores take credit card?
Politeness/Etiquette?

Any other advice on traveling and packing?

Thanks a lot!