Palm mute at the very beginning and slide down the neck from 
12th fret to open E 
 
 
e---------------------------------------| 
B---------------------------------------| 
G--------------------------------0h1-0h1| 
D----------------------------0h2--------| 
A------------------------0h2------------| 
E-12,12,12,12,12,12,12/0----------------| 
 
The "12," means you are picking the note very fast starting on the 12th fret 
and slide quickly down. Listen to the song for timing.