G-----------------|-------------------------|--------
D-----------------|-------------------------|--------(the other 7 beats
A-----------------|-------------------------|-------- of this bar are
E-2---2---3-------|-5---5---5---3---3-------|-3---3-- at the start)
  5 6 7 8 9 10 11   1 2 3 4 5 6 7 8 9 10 11   1 2 3 4

Every second time through this riff play    |-2---2-- instead of 3.

Alright, so play the above riff 3 times, then, when the lyrics start:

G-----------------|-------------------------|--------
D-----------------|-------------------------|--------
A-----------------|-------------------------|--------
E-2---2---3-------|-5---5---5---3---3-------|-2---2--
  5 6 7 8 9 10 11   1 2 3 4 5 6 7 8 9 10 11   1 2 3 4

     ****
G-----------------|-------------------------|--------
D-----------------|-------------------------|--------
A-----------------|-------------------------|--------
E-2---2---0-------|-0---0---3---3---3-------|-3---3--
  5 6 7 8 9 10 11   1 2 3 4 5 6 7 8 9 10 11   1 2 3 4

Alright, now play the above 2 riffs over and over for a while.

Then, when all the orchestra and stuff stops, finish at the end of
the bar with "****" above it and then play:

G-------------------------|------------------------|
D-------------------------|------------------------|
A-------------------------|------------------------|
E-0---0---3---3---2-------|---------2-------0------|
  1 2 3 4 5 6 7 8 9 10 11   1 2 3 4 5 6 7 8 9 10 11

Play the above 2 times, then play just the first bar again (but with
no 2)

Then:

G---------
D---------
A---------
E-3---3---
  1 2 3 4

Then play the intro riff over and over until the end.