Natural minor scales follow the interval pattern Whole step, Half step, Whole step, Whole step, Half step, Whole step, Whole step (WHWWHWW), with the first note (and last) in the scale determining the scale name. Finding natural minor scales on a guitar is a question of following this pattern on your guitar.
A natural minor scale is taken from the major scale of the same name, but with the third, sixth, and seventh degrees lowered one half step.
Playing minor scales on the guitar is simply a matter of following the pattern shown below. Play the notes in the number order shown below. Your first note is indicated by the 1 shown on the first E string.

Click here to download and print this diagram.
To play natural minor scales on the guitar, you just move the pattern along the neck of the guitar to build whatever minor scale you’d like. Whatever note you start with on the top (low E) string is the name of the scale. If you were asked to play an A minor scale on the guitar, for example, you would play the pattern shown below.
