This exercise 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 alignment and finger placement exercises for the left hand. Every guitarist should review this from time to time keeping an eye on these tips: Maintain proper finger placement with curved fingers, on fingertips, and close to the frets. The left hand fingers and knuckles should remain parallel with the strings. At first, play one finger at a time aiming for the perfect finger placement. After gaining some control, keep all fingers down until needed. When keeping your fingers down, be sure to release the pressure for every finger except the one being used. Keep the 4th finger down when you progress to the next string in order be legato across the strings. I recommend using i-m for the top three strings, your thumb for the bass strings, or i-m the entire time. These exercises can be played at any four frets of the fingerboard so feel free to play them in other positions.