Apart from major keys, the other basic tonality used in traditional western music is a minor key. Songs in a minor key use notes taken from a minor scale. There are three types of minor scale — the natural minor scale, the harmonic minor scale and the melodic minor scale. Written below is the A natural minor scale. The degrees of the scale as they would relate to the major scale are written under the note names.
The A natural minor contains exactly the same notes as the C major scale. The difference is that it starts and finishes on an A note instead of a C note. The A note then becomes the key note.
Memorize both the scale degrees and the pattern of tones and semitones which make up the scale, then play it with your eyes closed, mentally naming the degrees as you play.
Here is a melody in the key of A minor which is derived from the A natural minor scale. Learn it and then try making up your own melodies based on the ideas presented here.