As mentioned above, if your EHIC has expired you’ll need to reapply for a GHIC. We also recommend ensuring your insurance has relevant healthcare and repatriation cover, and double-checking that your passport has at least six months’ validity and is less than 10 years old. If you need to renew your passport, you will receive a blue, new-style one. A visa waiver scheme, much like the US ESTA programme, is set to be in place by the end of 2022. Under this, British travellers would pay a nominal fee for the waiver, which would be valid for two or three years.
It's also crucial to check entry requirements for the country you are visiting, as border control may require you to provide information such as proof of a return or onward ticket or sufficient funds for travel. It is also always advisable to check whether a visa is needed.
Finally, for many providers, free EU roaming has come to an end, so check with your mobile provider to find out about any roaming charges and how you may be affected.