It's like the background a painter uses before the foreground is drawn in. In the case of music, the background would be the textural patterns in the left hand. Then the right hand comes in "to paint" in the rest of the picture - in this case, the improvised melody.

George Winston used this approach in the piece "Rain." First you get this beautiful textural background created exclusively by the left hand. He covers more than an octave with the left hand using the thumb to reach past and make the music sound fuller. Now, in this piece he uses only a few chords, but interest is maintained through the improvised melody. In my piece, Flashflood, from Anza-Borrego Desert Suite, I use the same technique.

I start by playing an ostinato in the left, than add in the melody in the right. I keep playing the ostinato for as long as my intuition says, "this sounds good," then add in some contrast, either by changing chords, or by adding in new material.

It's important to realize that complete textural backgrounds can be created using the left hand alone. In fact, entire pieces of music can and have been created using this very versatile approach. It's especially suited for new age music. So, here's a step-by-step procedure for creating textures:

1. Choose your chords - These can be triads, or Open Position Chords, or any chord structure

2. Create a pattern for your left hand

3. Improvise a melody with your right hand