Color is a special feature of my design. Color provides a huge amount of key information in the design above. The drawing is dated, but still shows the basic idea. I now put a color dot on the white and black keys to simplify finding the right key and for ear training.
1. Note orientation: All the C's are marked with green, all the notes of the major scale are colored
it looks perhaps silly at first, but I've found guitarists "get" the chord structure in about 120 seconds, with the aid of the color scheme, instead of the normal 5-10 minutes I used to need.
It also works well with the way the brain hears music (think of it as Green= Doh = root, Red = So = dominant, etc); each note in the scale has a special feel when the ear knows it's place and color.
2, Key transposition: if you see a score with 3 flats, you play 3 black keys (Bb, Eb and Ab), and pretend they are "blackened" (a.k.a. flattened). If you see 2 sharps, you shift over to play 2 white keys. Transposition, which seems so hard on a piano, becomes utterly obvious on a coloured jammer.
3. Playing "Accidentals: as with key transposition, if you see a sharped note, move over to the "white"; three notes right, one down. Flats are the converse. It takes about a week for this to become automatic.
4. Musical education, helping arrange and create new songs, and provide insight, to name a few effects.
5. It looks interesting and cool.
6. Other things, which I will discuss later.