One of the biggest mistakes travelers make when it comes to spending is not having a budget for discretionary spending like food, entertainment and gifts.
Before you leave home, put together a general plan of how much you can afford to spend while you're on vacation. Average it out per day and then try to stick to it.
And don't pay for everything, or the majority of what you buy, in cash. If you're out of the country, you'll typically get better exchange rates when you use your credit card.
Sure, it's difficult to stick to an exact budget while you're on vacation, but if you keep a daily budget in mind, you'll be where you want to be and not find yourself overloaded with travel debt.
It's easy to spend money on knickknacks when you're having fun and the last thing on your mind is counting pennies. Still, if you keep track of expenses, you'll be happy you did in the long run.
Once you have that budget set up, periodically take a look at how you're doing. Pull out the receipts and credit card slips and add up how much you're spending. Do it a couple of times during your trip.
It's easy to overspend in the heat of the moment, but if you keep yourself accountable to the budget you set up, getting back home to bills you expect, not fear, will be a piece of cake.