For this, you only play the lower 3 strings (E, A, D)
Standard tuning
All the song is is picking the lower 3 strings

First part (before the vocals)
e|------------------------------------------------------------------------------------------------------------------------------------------------
B|------------------------------------------------------------------------------------------------------------------------------------------------
G|------------------------------------------------------------------------------------------------------------------------------------------------
D|--0---0---0---0---0---0---0---0---2---2---2---2---9---9---9----------12----12----12----12---8---8---8---8---10---10---10---10---11---11---11----
A|-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-9-9-9-9-9-9--------9--9--9--9--9--9--9--9-9-9-9-9-9-9-9-9-9--9-9--9-9--9-9--9-8--8-8--8-8--8---
E|2---2---2---2---1---1---1---1---0---0---0---0---7---7---7---7--9--10----10----10----10----9---9---9---9---8----8----8----8----9----9----9----9--
													    *				
This above is the first part, after this repeat it (the low and subtle vocals start at that point) 
Its a bit different at the end, so play the below when you get to the * I put down on the first part.

D|--10---10---10---1010--11---11---11---11-
A|-9--9-9--9-9--9-9-----8--8-8--8-8--8-8--8
E|8----8----8----8-----9----9----9----9----...

So bascially hit the 10nth fret on the D string twice there, and dont pause and stop on the end there because it now goes into the 2nd part.

D|---12----12----12----12---4---4---4-------7---7---7---7---11---11---12---11----12----12----12----12---4---4---4-------4---4---4---4---3---3---3--
A|--9--9--9--9--9--9--9--9-4-4-4-4-4-4-----7-7-7-7-7-7-7-7-8--8-8--8-8--8-8--9--9--9--9--9--9--9--9--9-4-4-4-4-4-4-----5-5-5-5-5-5-5-5-4-4-4-4-4-4-
E|10----10----10----10----2---2---2---2-4-5---5---5---5---9----9----9----9----10----10----10----10----2---2---2---2-4-5---5---5---5---4---4---4---4 (end)

Simple right? If anyone wants the notes to the song, in a weird format, what I originally jotted down, take a look below

F# C# D

F C# D

E C# E

B F# B

-> B C# D

D F# D

C# f# A#

C f# C

C# f C# ...

repeat above (with vocals), and after that play

D F# D

f# C# f# 

-> f# G# A

A E A

C# F C# (on 3rd go to D)

D F# D

F# C# F#

-> f# G# A

A D F#

G# C# F