It is highly recommended to call your bank about 2 weeks before your trip to let them know which countries you will travel to and the dates, so they won't block your card the first time you use it abroad. With some banks, you can do that online too.
Get a card with a chip at your bank before traveling. French credit cards all have a chip.
It is highly recommended to carry at least 2 credit cards, if possible from 2 different banks - in case one fo your card gets temporarly blocks for any reason, you have back up.
Ask your bank if they have an agreement with a French bank for cheaper transaction fees. It is often the case with the biggest banks.
Have a contact to your bank handy while traveling, in case you need to reach them.