In lack of a regular check flight as well as of an appropriate instructor while flying in the South American bush, I devised a series of "Emergency Cards".
Each of the playing card-sized works of art consisted of one kind of troublemaker known to spoil a pilot´s joy of flying at the most inappropriate moments.
They were meant to be displayed in front of my eyes by a passenger any time he chose during the flight. This makeshift check-pilot could then verify whether my reactions, commented aloud, were confirmed by the answer found on the back of the card.
Sometimes it took a little coaxing to get a non-flying passenger to pick an emergency card from the deck! They must have felt like gambling with their own lives.