Watch the SECTION 1 : Solo Arrangement Basics online guitar lesson by Fareed Haque from Solo Guitar Handbook
I don't really like even calling this approach to solo guitar a "system", it's really just what you do to learn a song on any instrument. I'm just organizing it a bit, so we don't skip any steps. Maybe we can call it a natural process, not really a "system". Learn the melody, learn the basic chords, put 'em together. Build fancy chords and chord progressions from the simple ones, add an intro, outro runs, and fills, and there you are!