How do you get medals in Star Fox 64

You get medals by getting a certain amount of hits in each level.
The amounts are:
Corneria: 150
Meteo: 200
Fortuna: 50
Sector x: 150
Titainia: 150
Blouse: 150
Venom: 200
Katina: 150
Solar: 100
Macbeth: 150
Sector y: 150
Aquas: 150
Zoness: 300
Sector z: 100
Area 6: 300
Venom 2: 200 (Venom 2 can only be reached if you go through Area 6)