Improvisation Practice Concepts 1 and 2 - ranges, contrary motion
Practice Concept 1 - ranges
Before you play anything, pick a range of notes that your right hand (or melody voice) will play. Then you must stay within the range. Do this during improvisation, or during a tune, either way. It will be hard, and that's what we need- restraints. Just like athletes train by focusing on one part of their body ("specificity"), we must train by focusing on one concept.
This is “structure in chaos” illustrated.
Practice Concept 2 – Contrary Motion
Recently I’ve thought about how little attention I paid to this concept, even in music theory class in college. Why don’t you look out for two or more lines moving in opposite direction, in all the music you listen to—it’s not very often there is it? Not in today's culture.
But it was very present, in part-writing in the time of the Monks of the middle ages in Europe.
Now try playing just two notes or lines at once, and make most of the movement in opposite directions. See how little you’ve ever played that way? Most of the time we play things in one direction with both hands. In fact, music teachers like me usually start teaching people that way, simply because that's the way we were taught. It's a shame we keep repeating history, really. Try being different. It will pay off.