Some of you are seasoned travelers and you already know what to expect on this trip. On the other hand some of you may not realize how different things can be in other parts of the world. I'll use this page to post suggestions from my own perspective.
1. Electricity. Do not take electrical appliances (hairdryers, etc.) Europe operates on 220volts not 110volts like in the U.S. The outlets are a different configuration and your plugs will not fit. Even if they did fit 220 voltage would blow out your 110 appliance. If you have a small appliance that you cannot live without you can purchase a small electrical converter. Both hotels have hairdryers in the rooms.
2. Cameras/Video. If your camera uses rechargeable batteries you should make sure the battery is fully charged before you leave. If possible you should bring a second battery. You won't be able to recharge them using European electrical outlets.
3. Tipping. The system of tipping at restaurants is different from in the U.S. Tips are appreciated but they rarely equal 15% of the bill. When the bill arrives simply round up the amount to the next whole Euro. If you want to leave a tip find the waiter/waitress and give it to him/her personally. A tip is usually one or two Euros, not a percentage of the bill. Never leave it on the table and walk away. Leaving money on the table gives the appearance that you are leaving the waiter your scraps. A tip is a personal way of saying thanks for good service. It is not the same obligation as it is in the U.S.
4. Money. Both Italy and France use the Euro. Expect the prices to look similar to dollars. "Dollars" and "cents" are separated by a comma, not a decimal. They use a decimal to separate thousands from hundreds so if you see a decimal you probably can't afford it. ($1,599.00 would be expressed E1.599,00) An item that you would expect to cost 10 dollars will probably cost about 10 Euros. The difference is that it costs 1.50 US Dollars to buy 1 Euro. The number "1" is not a straight vertical mark. It looks like an upside down letter "V". Taxes are always included in the price so you pay exactly what you see. If you cannot understand the price in Italian or Greek the store owner will type the price on a hand calculator and show it to you.
Don't take large sums of U.S. cash. You will lose most of it in the exchange. Currency Exchanges (found in all tourist areas) charge a transaction fee PLUS a percentage of the money. Find an ATM or bank and use your bank card or credit card. It is just like using an ATM in the U.S. Don't take out more money than you will need because you will lose on the reverse transaction as well. Notify your bank and your credit card companies before you leave. Otherwise they may be suspicous of foreign charges and deny the transaction.
England still uses the British Stirling or pound. The pound is worth 1.67 US Dollars. Again, don't stock up on currency. You can trade it back at a currency exchange but you'll lose most of it. Currency exchanges do not change coins.
6. Restrooms. It can be difficult to find public restrooms in the cities. Use the facilities at the restaurant or museum. Even if the locals speak English they do not use the terms "restroom" and "bathroom." Use the term "toilet" (toletta) or "water closet" (gabinetto) instead.
7. Weather. The European climate is generally mild but one never knows about weather fronts. Average high/low temperatures in Venice in late March are 59/42. Paris and London temperatures will be similar but the chance of rain is much higher, especially in Paris . Check weather.com immediately before our trip for the possibility of storms/rain.
8. Clothing. Obviously you should dress for the local weather. Late March in Europe would compare to late April in Eau Claire. A light/medium jacket is suggested but you might only use it at night.
As for style ... try to blend in. Italians and French are fashion conscious and they dress up in the cities. Wearing jeans is perfectly appropriate but jeans are usually dressed up with a wool blazer or peacoat. Italian/Greek jeans are never ragged or baggy. Clothes are FITTED to the body and generally dark in color. The stereotypical American tourist wears baggy jeans or cargo pants with a brightly colored shirt/jacket and white sneakers. Don't be that guy. Europeans wear dark colored clothes that are fitted to the body with black shoes.