Minor Chords

By now you should have done the rounds of the major (root 3rd 5th)
and the power chords (root and 5th).
The way to form a minor chord is to take a major chord and flatten the third.

Form a major, make sure you know which note is the third and move it down by a semi-tone (1 fret).
So a minor is root, 3rd flattened and 5th (plus any of the notes repeated).
Example: G minor

1	3-	5
G	Bb	D

In theory then, just moving one finger down one fret turns a major into a minor.

See a List of Minor chords