/ means strum alot (about 8 times in this song just listen to the record) 

the main riff 
G|---------------------------------------------------------------------------| 
D|---------------------------------------------------------------------------| 
A|-----/4------/7-------/2---------------------------------------------------| 
E|-----------------------------/2--------------------------------------------| 

sometimes it does this 
G|---------------------------------------------------------------------------| 
D|---------------6-7-6------------6-7-6--------------------------------------| 
A|---/4------77---------7-----77---------7------/2---------------------------| 
E|------------------------------------------------------/2-------------------| 

Chorus song ends on 
G|---------------------------------------------------------------------------| 
D|---/2-----/4---------------------------------------------------------------| 
A|-----------------------------------------------------4---------------------| 
E|---------------------------------------------------------------------------|