How can I change the colour of the Airplane Symbol

In order to find my way around an airport (taxiways, runways, etc.) I usually enlarge the airport layout on the G1000 MFD. Now starts the problem : many areas, such as ramps, taxiways etc. are depicted in white and so is the aircraft symbol which then cannot be distinguished anymore from the background. To remedy this problem it would be necessary to change the colour of the aircraft symbol. How can this be done ?

Hans B.