This song is amazing. Standard tuning (EADGBE).
First bit (the higher-up part):
E:------------------------|------------------------|
A:------------------------|------------------------|
D:------------------------|------------------------|
G:--------8s10------------|----10-10-10s8-8-8s7----|
B:---------------11-------|------------------------|
E:------------------------|------------------------|
[ Tab from: http://www.guitaretab.com/s/structures/322570.html ]
E:------------------------|----------------------------|
A:------------------------|----------------------------|
D:------------------------|-------------------------8--|
G:--------8s10------------|----10-10-10s8-8-8s7--------|
B:---------------11-------|---------------------8p6----|
E:------------------------|----------------------------|
Second bit:
E:------------------------|
A:------------------------|
D:--8s10--5---5s3--3--3s8-|
G:------------------------|
B:------------------------|
E:------------------------|
And that's it! Just repeat those two parts. Make sure to add lots of reverb to get that
lovely ethereal feeling.