Important: Certain Degrees are minor and certain degrees are major.
How we get the chords for a certain key:

• Take the major scale of a certain key (example: C major scale for the key of C -- shown above)
• Look at the Chords for the I degree, Now form those chords from the I note, which is C
• You get C Major and C Major 7 notice that the notes of these chords are in the C major scale
• You can use other chords but the ones I will show are the basic ones. I did this to simplify things
• Now notice that the II degree uses Minor and Minor 7 chords. But this time, instead of using C we use D to start the chord because it is the II degree of the major scale. So we can use D Minor, and D Minor 7 with the key of C. (Remember to go to the D Major Scale to find the D Minor and D Minor 7 chords).
• You can continue down the chart to find all of the chords.
• You might want to write them down too.

Using these Chords:
There are some standard Chord Progressions. Such as a Blues Progression --> I - IV - V
Try playing C major, F major, then G major chord together.
Now try playing a I - III - IV - V progression using C major, E minor, Fmajor, G major.
Notice that the III was an E minor chord because the III degree is minor.
Try making up your own progressions. Have fun with it. but
Remember: I, IV, V are Major and II, III, VI, VII are Minor

These all sound good because they're in the same key. They're in the same key (C) because all of the chords that you went down the list with earlier use the same 7 notes which are the notes of the C major scale.

• Here is a chart that lists the chords that can be used to represent each degree and still use only scale tones.