by Logan Young
1) Know the genre you want to learn for improvisation.
One of the best ways to find out the genre that appeals to you is by listening to a few styles (i.e. jazz, blues, rock, folk, country, pop, etc.). The ones that stick in your mind are the ones to start off with. Like with anything you learn, learning becomes easier when you're interested in it. As you listen to the various styles, one thing to keep in mind is that the blues genre relates to most all the other genres. For that reason, if you learn to improvise in the blues genre, it will ultimately end up helping you improvise across all the genres.
2) Build up a foundation of jazz guitar licks and riffs.
Successful players have built up a memorized library of licks and riffs. During their jazz guitar lessons, they have absorbed and practiced these licks from a variety of sources so that when it comes time to perform solo or lend an improvisation, they are ready to practice and apply what they have learned. Improvisation becomes easy because they know how to blend tunes on their gypsy jazz guitar.
3) Knowing the scales is the foundation for improvisation.
No jazz guitar player can improvise without knowing their instrument and how to craft the melodies together. When learning to play jazz guitar, you can't ignore this important step. You don't have to learn all the scales. In fact learning just a few scales like the major scale and the blues scale will be sufficient for a lot of improvs and solos. For example if you can see a lick in and filter it through the major scale, you'll have mastered what makes a jazz guitar player a jazz guitar player and your audience will appreciate your talent and effort!
4) Transcribing tunes are a great source for improvisations.
Transcribing involves learning a tune by ear and then working it out in different chords if you choose. Transcribing really helps any serious player and should be a regular part of their solo practice. It involves trial and error practice where you'll discover what works for you and what doesn't work.
5) The best part is hearing yourself play.
Inspire yourself during your improvisation by recording yourself (you might also consider hooking up jazz guitar amps). When you listen to the recording, you'll be able to hear even better the areas that need work. At the same time, you'll also hear the areas that work very well and demonstrate the progress you've made as a jazz guitar player.
Improvisations and solos are like a string of musical ideas that you have gathered along the way through your learning career. You'll get these musical idea? by learning and mastering the scales, learning to key licks and riffs and by transcribing tunes that you enjoy. You'll soon see your creativity and skills take off!