[kazinator]

The basic idea: fret a string on one of the indicated spots in the diagram, pluck a string. Then pick another one, and do the same thing; now you have a melody starting.

Moving on: divide that pattern into interlocking "boxes", and memorize the fingering pattern for each box, and how it dovetails with the adjacent boxes.

Some boxes have a transition where there are two notes per string; this is good for staying in a tight position, without much finger stretch. Three-note-per-string boxes are good for shredding.

If you have this overall pattern memorized and well rehearsed under your fingers, you can easily improvise to most music (at least that with Western roots around diatonic scales). Listen to the track and play a few notes by ear. Within a bar or two, it's obvious which pattern you are in and from there you know the rest of the picture instantly, and can "break out" all over the fretboard.