Practice slowly at first in order to develop an early aural and technical accuracy. Isolate difficult and weak passages or motives and practice them many times over until you have complete control over the music. Practice each assigned piece and exercise daily . It is the foundation upon which the understanding of basic scale and chord theory is based. Theory is the study of how music is constructed and is essential in the improvisations of blues guitar playing.
Improvisation is the spontaneous creation of music within the structure of music theory.
Play F on the 1st fret of the 1st string . Now play G on the 3rd fret of the 1st string . The distance from F to G is said to be one whole step . A half step on the fingerboard is the distance of one fret from a lower note to a higher note or one fret from a higher note to a lower note. Play E on the 2nd fret of the 4th string .