When going abroad it is important to have a valid passport. When travelling outside the EEA it is very important to find out whether a visa is required, sadly we receive some complaints from travellers who, lacking a visa, have been sent back home. Also many countries outside the EEA deny tourists entrance unless their passport is valid for 6 months after their travel ends.
It is always wise to travel with the European Health Insurance Card, but citizens from the EEA should be able to get the card from their social security, to access state healthcare in other European countries at reduced fees or for free. If you are visiting another part of the world find out what your insurance covers, and whether you need any medication or vaccination.