This is the main riff throughout the song. You can hear it clearly at the beginning of 
the song:

G|---------44444444--------66666666---------44444444-----------------|
D|-44444444--------77777777--------44444444---------7777777766666666-|
A|-------------------------------------------------------------------|
E|-------------------------------------------------------------------|

Around 2:32 - 3:12 comes a part where I don't hear the bass playing. Use it to 
improvise: use the notes above to play something slow.
I personally play something like this:


G|-------------------------4~-----------------------------4~------|
D|-4~------6~------4~--------------4~------6~------4~-------------|
A|----------------------------------------------------------------|
E|----------------------------------------------------------------|

G|-------------------------4~-------------------------------------|
D|-7~------6~------4~--------------7~------6~------4~------4-4-444|
A|----------------------------------------------------------------|
E|----------------------------------------------------------------|

G|-4-4-444-4-4-444-----------------4-4-444-4-4-444----------------|
D|-----------------7-7-777-7-7-777-----------------7-7-777-6-6-666|
A|----------------------------------------------------------------|
E|----------------------------------------------------------------|

Then you play again the main riff. hope you enjoy :)