20 Choruses Over Honeysuckle Rose
Sometimes, it can be really advantageous to choose a song and improvise for a long period of time, with a plan. 20 choruses is quite a bit of time to improvise, and by then end, (if you record yourself), you will learn a lot about your own improvising. You'll notice your habits, what things you need to work on, your strengths and your weaknesses, and you'll be better for it!