Text ROAMING to 150 (it's free) before you travel.
You'll get a text either confirming you're set up, or telling you how to set up roaming on your device.
Tablet and 4GEE WiFi customers can check if they're set up to use roaming by calling +44 7953 966250 from a mobile before you travel. Local rates will apply, or you can call 150 for free from an EE mobile
Remember - roaming can take anything up to 24 hours to become active on your account, so it's really important to check you're set up well before you set off.