The safest form of taking money abroad is to use Travellers Cheques. Typically available in denominations of 10 £$€, 20 £$€, 50 £$€ and 100 £$€, these can simply be signed for (you will need some form of identification, ideally a passport, to do so) and cashed in.
Replacements are available quickly should you lose them or have them stolen making them a far safer method of taking money abroad than currency alone. If you use these rather than cards, you have the added advantage of knowing exactly how much you’ve spent and how much you can afford to spend.
Even if you plan only to use Travellers Cheques or Credit/Debit cards, it is wise to make sure that you have at least some foreign currency to hand before you set off.
Taxis, drinks on arrival, road tolls, tips etc. all need to be paid for, and the chance of them all able to accept a cheque or card – zero! We would recommend a minimum of around 50 £$€ worth of foreign currency (try to get hold of coins as well as notes) and this should be enough to get you by, but of course taxis and transfers can impact on this in a big way. With this in mind, be sure to do a little advance planning before you set off on honeymoon so you don't get caught short before you even arrive at the hotel!
Credit and Debit cards are accepted the world over, though be aware that some are accepted in more places that others and in off the beaten track destinations, some may not be accepted at all! That said, they are still a very convenient form of honeymoon money, so rather than lumping around a huge wad of cash each night, you may want to consider just talking your plastic friend instead!