i don’t think someone will getting lost in london, as the city is very informative and easy to be traveled [http://www.tfl.gov.uk/gettingaround/default.aspx]. when you finished for border and luggage things in Heathrow, to go to london city is just hop on tube, it’s LRT. with Piccadily line from Heathrow terminal 1,2, 3 and 4 we can reach the city of london only in 45 minutes.
as the transport fare is expensive, travelers are suggested to buy travelcard or oyster card so that you can freely hop on and off every bus, tube and tram without paying ticket anymore. and if you’re in something don’t know where to go, you can ask the officers, they will help you to find the best direction. so get lost in london? why not?