Watch the Pick & Fingers online guitar lesson by Jennifer Batten from Rock Sauce for Rhythm Guitar
The progression for the first part is the same as Stairway to Heaven: A minor, A minor major 7, A minor 7, A minor 6. But, aside from the A string pedal, I'm only using the middle two strings for the harmony instead of strumming the entire chord. I use my second and third fingers of the right hand to get a little skin under the strings to snap the notes outward. Whenever you have a pause, add some vibrato sauce to enhance the groove.