Celebrity Christopher Biggins had another tip, but it might land some passengers in hot water.
He said: “What you should do is give your passport with a £50 note in it. Hand it over to them and they either have you arrested, or put you into a first class ticket.”
However, former flight attendant and Love Island star Amy Hart, said: “The best way to get upgraded is to pay for it.”
Passengers seated in first class can also gain access to exclusive airport lounges at most major airports.