Riff 1
E|--0-0-2-2--0-0-2-2--0-0-2-2--0-0-2-2--0-0-2-2--0-0-2-2--0-0-2-2-------|
B|----------------------------------------------------------------------|
G|----------------------------------------------------------------------|
D|----------------------------------------------------------------------|
A|-----------------------------------------------------------------2~---|
E|----------------------------------------------------------------------|

Play Riff 1 four times then play....

Riff 2

E|-------------------------------------------------|
B|-------------------------------------------------|
G|------------------------4-2---2------------------|
D|------4-2-4-----4-2-4-------4---4----------------|
A|-----------------------------------2~------------|
E|--2-2-------2-2----------------------------------|

Repeat twice then play Riff 3....

Riff 3
E|-------------------------------------------------|
B|-------------------------------------------------|
G|-------------------------------------------------|
D|------6-4-6-----6-4-6----------------------------|
A|-------------------------------------------------|
E|--4-4-------4-4----------------------------------|