If you want to l earn how to play the blues guitar, then you probably also want to be able to play blues improvisations. Getting tuition from someone like Scott Henderson would be a good place to start. That being said, some people simply prefer learning on their own, and that is actually not too difficult to do with blues improv. In fact, you can learn how to play them even if you’re not an accomplished blues guitarist.
Your starting point has to be on technique. If you don’t get that right, you may as well not bother at all. Improvisation is about a lot more than simply playing random notes. You have to know what the scales are and your notes have to be based on that, which requires technique. The best way to learn about this, besides going to school, is to listen to your idols over and over and over again. The likes of Eric Clapton, John Lee Hooker, Van Morrison, and Mark Knopfler are all excellent example of blues guitarists that you can learn from simply by listening. Once you figure out their techniques, you can base your own on those and create something truly unique.
Do make sure you choose more than one idol, because they all have different techniques. Ideally, you will be able to mix their styles together to create something. Also, don’t focus solely on blues just because you want to learn blues improv. All music styles are developments and evolutions, and there were things before blues, and other things have come after. Study all of those.
There are two key things to know about blues improv:
The important thing is that you start at the first point. It may be a slow, long and tedious process, but you must make sure that you have the technique sorted before you start creating your own, or it will be a hot mess. Once you have learned technique, you will find everything else starts to flow.
Another cool tip is to change the scale of your guitar and listen to a lick that you enjoy. Then comes the boring part, which involves practicing every single note again and again, until you can literally play them in sequence with your eyes closed. Once you have that down, you can start improvising in some of the parts of the lick, and pick the existing one back up if you go wrong. Start simple: omit a couple of notes, or repeat a few others. Remember that the guitar is about having fun as well, and while all learning involves boring repetition, it does pay off at the end.
The style of blues is an amazing style that thousands of people the world over enjoy playing. It lends itself perfectly to improvisation, and you can learn to do it quite quickly yourself. Just practice and keep it up.