Intro, Verses, Outro: Power chords G, G, D, C, C
But play the 2nd verse and outro without and octave and open, like so:
  G D C
|-0-0-0-|
|-0-0-0-|
|-0-0-0-|
|-0-7-5-|
|-5-5-3-|
|-3-----|

Chorus: G, D, C, C
On the 2nd C use your little finger on the 3rd fret on the high E string. Listen for the 
rhythm.

Thats it! Enjoy!