London is one of the most beautiful cities in the world but to enjoy it to the fullest before leaving it is good to know three basic things that I have learned that have allowed me to visit the city well without too many hitches. Among the first things you should never forget is an adapter to the power outlet! : D
Remember the time zone, when you arrive in London it will be an hour behind most of the rest of europe and if you have an iPhone or phones that you update yourself I recommend you don’t forget updating them because during a journey times are important: subway, train , museum schedules and many other things.
Do not forget to change the currency before you leave. About this experience I’ve already had my say in another post and I think it is better to change before a few pounds. Note though that if you have to go to the post office they just will not have much cash available so maybe take the minimum and try to pay with cash once in London.You can find an ATM across London and really use it anywhere.
With regard to the adapter as I mentioned before try not to forget it. There are also many international adapters and buying one of those you can use in all parts of the world even in London will save you a lot of frustration. If you go to a hotel and you have forgotten to bring one, they may provide you with one, though sometimes unfortunately they charge. If you’ve got an apartment then you will have no choice and you will have to go and buy one. Always best to bring your own.