I couldn't find the very beginning of this song, so decided to have a go at tabbing it. 
It's my first ever tab - hope it's okay!

Main riff

e|-----------------------------------|
B|-----------------------------------|
G|-4-4-4-4-4-4-4-4-4-4-4-4-4-2-1-2-3-|
D|-----------------------------------|
A|-----------------------------------|
E|-----------------------------------|