As you probably know, every major scale has a “kissing cousin” — a minor scale that is related to it’s major scale. To locate the starting point of a minor scale, find the 6th degree of any major scale and that becomes the root (the starting note) of it’s relative minor scale.

For example, in the F major scale the 6th degree of that scale is D, so D becomes the starting point of the relative minor scale to the scale of F, which of course is D minor.

Watch this short video and I think it will become clear to you:

For more information on scales, take a look at All About Scales & How To Use Them!