Call your bank and credit card companies to inform them you will be traveling before you go overseas. They may require written authorization from you to clear transactions initiated in a foreign country. Without this, many financial institutions will refuse unexpected charges to your account from a foreign country. They may require prior authorization even before you book accommodations abroad on your card.
Ask your bank to temporarily increase the purchase and cash advance limits on your ATM card, if you think you might need an increase while abroad.
Devise a safe place to keep your cards. Wallets and purses are easy targets for pickpockets. Many luggage and travel sites sell special pouches for keeping money and passports under clothing. Read consumer reviews before purchasing any of these and consider the climate. In summer clothes it's tough to conceal anything as unwieldy as a passport, though the cards can be easily hidden.
Keep money with you. Do not leave money, cards or passports at your hotel unless they are in a locked safe.
Keep a stash of local cash available so you don't have to take your cards from their hiding places.
Use ATMs the same way you do at home, with caution. You may have to start the transaction by choosing your what language you want. The ATM will dispense money in the local currency. Withdraw as much as you can reasonably keep safe. Not only will you possibly pay ATM fees but you will also pay a small currency exchange fee every time you withdraw cash.
