This is from my new book Classical Guitar Technique: Essential Exercises, Scales, and Arpeggios. The 122 page book includes: Practice Routines, Tips, 100 Open String Exercises, 120 Giuliani Arpeggios, Scales, Slur Exercises, Shifts, Finger Independence, Barre, Tremolo, Common Harmonics, and much more.
This lesson is on chromatic scales and variations and follows the alignment and finger placement exercises for the left hand. Chromatic scales are great practice for putting the one-finger-per-fret hand position into action. Remember to go slowly (at your own speed for your level) and aim for a smooth legato sound. When shifting, keep the thumb behind the 2nd finger and have the arm move the hand up and down the neck without altering your hand position.