This is the main riff. It's played the whole way through the song. it's pretty easy.
for the beginner.
E|--------------------------------|
B|--------------------------------|
G|--------------------------------|
D|---3-3-3-3-2-2-2-7--------------|
A|---3-3-3-3-2-2-2-7--------------|
E|---1-1-1-1-0-0-0-5--------------|