If you watch his fingers, you can see his chording. His first chord is a D, but with his capo at the 3rd fret that puts him in the key of F. To play it the way he did, place the capo on the 3rd fret, for a verse play D, A, Bm, A, G (you'll play that sequence TWICE) and when you get to the chorus, play Em, G, D, C, G D, C, G. When I sing the song, I'm either in A (capo at 2nd fret, play G chording) or Bb (capo at 3rd fret, play G chording), but for me my first chord is a G, not a D.
