Okay, play this only once the first time

D-777-

Then, do this (main riff)

G-------------------------------------------------------
D-777----888-888----999-999----101010-101010-----121212-
A-------------------------------------------------------
E-----10---------10---------10----------------10--------

When the music changes (chorus), do this

G-------------------
D-121212-----121212-
A-------------------
E---------10--------

When the guitar returns to the main riff, continue for a
few measures, then when you hear it change slightly
go back to the main riff

Later on when the guitar repeats the chorus you play with it

G--9-7---------------------
D-------10-777-55-33-320-
A--------------------------
E--------------------------

During the bridge(1) you play this

G---------------------------------------------------------------
D----------------7/(0)------------------7/(0)-------75----------
A--0---0---0-----------0----0--0--0-----------0----------75--35-
E---------------------------------------------------------------

On the fadeout and the second bridge you play

E--3--5--

on and off (listen for it and you should get it)