G|-----------------|
D|-------5-6-5-----| Pattern
A|---5-8-------8-5-|    1
E|-6---------------|

G|-------5-6-5-----|
D|---5-8-------8-5-| Pattern
A|-6---------------|    2
E|-----------------|

G|-----------------|
D|-----------------| Pattern
A|---5-6-7-8-7-5---|    3
E|-8-------------8-|

The main part is just:

Pattern 1 x 2
Pattern 2 x 2
Pattern 1 x 1
Pattern 3 x 1
Repeat throughout the whole song, basically.

After one of the verses, he plays:

G|------------|
D|------------|
A|------------|
E|-6--7--8--7-|

And then later in the song, the key shifts up a minor second, which means you just play 
up one fret. So instead of walking at the 6th fret, it'll be the 7th fret, etc. etc.