Anyone who has been to a live concert that involved guitars will have heard some improvisation. When music is improvised, the artist simply expresses their feelings through their instrument, without following a set of notes. This can be done in any style you like, although it is conventionally done in jazz. People like Scott Henderson are particularly adept at it, and if you were to get a chance to learn from someone like him, you would really be very lucky.
How to Learn Improvisation
If you don’t have the opportunity to learn with Henderson or someone like him, you can actually learn it yourself. Your starting point has to be to understand the scales on a guitar. Improvisation is anything but random, and players don’t simply hit a few notes and hope they sound good together. Rather, players will follow certain scales, and, when framed together, they will form a melody. Hence, your starting point should actually be to look at the neck of your guitar and the frets, and figure out where the different scales are.
You can choose from a range of different scales, with most people starting with the pentatonic one. Once you know which scale you want to play, and what the chord sequence is, your improvisation will also start to flow. Not just that, however, but when you practice your scales, your fingers will start to have muscle memories, so they will automatically know where they should go. When you improv, you will play a solo and melody on the spot, so you won’t have time to look at where your fingers are going.
Next, you have to learn about arpeggios. Those are not series that, when put together, create a chord. However, you don’t play them at the same time (it would be a chord then), but you play them in sequence after one another. This is really useful, and quite easy to use as well.
If you really want to be good at improvisation, you have to practice and practice again. If at all possible, do also practice with accompaniment. If you don’t have friends who play instruments, you can simply put on some background music and follow that. This is absolutely necessary to help you figure out how to time and execute your improvisation. Practice will help you build your personal technique, as well as your understanding of rhythm.
There are some excellent books that you can refer to if you want to learn to play improvisation but can’t take lessons. Those books are designed to help you understand the theory behind the scales and the arpeggios. Online resources also exist, including online guitar lessons. YouTube videos, for instance, can run you through scales and arpeggios step by step. The best thing, however, is to take lessons from an experienced player like Scott Henderson. There simply is no substitute for direct teaching and education, and for the feedback you will be able to get about your playing.