You'll probably want to call into Customer Care to discuss this, because there may be different plan options that vary with your phone model, but if this is just for a trip, then all you should need is the International Travel Pay As You Go feature, which will charge by the minute/text/MB used when out of the country. You'll also need to make sure you enable Data Roaming in your phone settings before leaving the U.S., and if trying to avoid using the mobile data, I'd recommened turning it off altogether to keep background data from adding to the Pay As You Go charges. If you want to add the feature yourself, or if you need to add a more long term plan for international services, you can make the change on the Verizon Wireless website:
My Verizon > My Plan & Services > International Usage & Services
