Like William said you need to know the notes on the 6th string and I would say the 5th also. From there I start with the L and inverted L from the beginner courses. This gets you to the chords in the scale. I know that the only the 1, 4 & 5 chords are the same, meaning major or minor. So in C major the C, F & G are major. In C minor the C, F and G are minor. From there you just need to know the steps and that the 7 is diminished in Major and the 2 is in minor.