Originally Posted by
Ldnn1
If flying from LGW, don't use the Gatwick Express as it's way overpriced. If Victoria is convenient for you just take a Southern train, which takes basically the same time as Gatwick Express but is cheaper, or take a Thameslink train from Kings Cross St Pancras, Farringdon, City Thameslink or Blackfriars if any of those are convenient for you.
Or consider
EasyBus, which if booked sufficiently early, can be as cheap as £2 per person each way between Gatwick and London. It should go without saying - allow PLENTY of time for your transfers - choose a bus that will get you back to the airport earlier than you really need to be there.