Watch the A Form For All online guitar lesson by Brad Carlton from Chord Studies: CAGED Chords Vol. 1
This example applies the A chord form out of the CAGED system to play both an A and a G chord. Each chord is played for four beats, so start out simple enough to make the changes clean and then start to introduce more rhythmic variation. Note that the A chord in the 12th fret is the octave of the standard open position A chord.