Practice writting melodies and riffs in the different modes. It's just like writting in the major scale although you use the modes instead. Here's an easy way to think of it.
The difference between modes and the major and minor scales is simple. Take C major, which has the notes C D E F G A B C. Now take C mixolydian and you get C D E F G A Bb. Only one note changed, the 7th. So now just think of C major, but if you the 7th (B), play it down a step.
Each mode except one is closely related to either the major or minor scale, with one alteration. Learning this alteration is a quick way to learn them.
Major modes - Ionian (major scale), lydian, and mixolydian
Minor modes - dorian, phrygian, and Aeolian (natural minor)
Locrian is diminished.
This is easy to see if you know the harmonic sequence of a major scale, and which mode goes with which chord.
Here's the major harmonic chord (in roman numerals[ small letters are minor, capital letters are major]).
I ii iii IV V vi viio (viio is diminished)
Once you get an idea with writting melodies in the modes, go for this.
Write some chord progression in a major scale. and instead of thinking of just using the major scale, use the appriate mode over each chord.
Ex. say your in C major and you have this progression.
| C . . . | F . . . | C . . . | G . . . |
Instead of thinking C major over the entire progression as you solo or build a melody. Use your modes. C major scale over the C chord, F lydian over the F chord, and G mixolydian over the G chord.
Once you get used to that, pick up a Jazz impro book or jazz lead sheet book and apply the same thing. You'll be doing the same thing, but on a deeper level.
This is because Jazz uses alot of modal modulation. This combines the two things I just wrote about, and what you already preceived when you first wrote this post.
Modal modulation is changing the mode for each chord. Remember I said there are three modes that are relative to each the major and minor scale. So if you have a chord like F major, you could use 3 different mods over that chord, Ionian(major scale), lydian, and mixolydian. Regardless of it's function in the key of the song.
F major in the key of C major is the IV chord, or lydian. However you can use the major scale (ionian), or the mixolydian mode over that chord. Here's what you got before.
Say you use the F mixolydian over the F chord in the key of C major. F mixolydian has the same notes as the key of Bb major. So while you use the F mixolydian you are changing keys, hence modulation by the use of modes.
Interesting, eh?
As you can see modes will take you pretty far and open you up alot to tons of possibilities. Modal improvistion is pretty cool because it makes for interesting phrasing.
Now the reason I didn't give you a text on modes, is because reading about it alone won't help you. Learning music is about application, you have to apply what you just read to fully get it. Have fun! :)
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