Traditional 'lost procedure' was fine and dandy in the days of Tiger Moths when there were few airways and even less controlled airspace about which to worry.
These days the best course of action is to admit to yourself that you're lost, then get on the radio and ask for help. Otherwise you stand every chance of becoming an infringement statistic in most of the UK.
The student diversion to Cranfield was a classic example of what people should be taught!