How to be a good improviser; good question. I think to start, you need to learn to be a good listener. Listening is the key to improve; being able to recognize chord progressions, follow dynamics, and blend with the other instruments in the band. Listen to the rhythem section. Your sense of timing is critical in improvisation. Practice scales and fingerings. Understanding scales is a big part of improv. I would suggest taking a music theory class. Also, listen to your favorite performers and their techniques. Then, use theirs to develope your own style. Once you've come to understand basic theory and you are more familiar with scales, just play around and have fun with it! You'll soon decide what works and what doesn't. Jim