Three main parts:
1 Intro and ryhthem drone chop:
E-|-------------x---| Heavily palm muted. During verses let A string B-|-----8-----------| ring and fret E string with thumb over the G-|-------------x---| top (T). D-|-------10--------| A-|-------------x---| E-|-----T-------x---|
2 Power chord crunch:
E-|---------| A major at the nut. B-|-----3---| G-|-----3---| D-|-----3---| A-|---------| E-|---------|
3 Descending line in change:
E-|-----------------------------------------------| B-|-----------------------------------------------| G-|-----------------------------------------------| D-|-------7-5----7-5----5-4----3-2----0---0-4-5---| A-|-----0------0------5------3------0---3---------| E-|-----------------------------------------------| etc... continue from open A string.