Learning Modes - Some formulas

Once you start getting the idea of modes, one of the easiest ways to deal with them is knowing how they are spelled relative to their ionian version. We can Use the key of C as a great example.

C Ionian     C  D  E  F  G  A  B    C Major
C Dorian     C  D  Eb F  G  A  Bb   Bb Major
C Phrygian   C  Db Eb F  G  Ab Bb   Ab Major
C Lydian     C  D  E  F# G  A  B    G Major
C Mixolydian C  D  E  F  G  A  Bb   F Major
C Aeolian    C  D  Eb F  G  Ab Bb   Eb Major
C Locrian    C  Db Eb F  Gb Ab Bb   Db Major

Since C Ionian has no altered notes, we can use that as a very nice baseline

Ionian      - No Changes
Dorian      - b3 b7
Phrygian    - b2, b3, b6, b7
Lydian      - #4
Mixolydian  - b7
Aeolian     - b3, b6, b7
Locrian     - b2, b3, b5, b6, b7

So if we simply apply this formula to a major/ionian scale, we transform it into that mode.