This is basically the whole song right here: 

Standard tuning: eadgbe
     Just keep playing this part throughout the whole song!

E|-------------------------------------------------------------------|
B|-------8---------8-----------10---------10-------------------------|
G|-------5---------5-----------7----------7--------------------------|
D|--5--2------5--2--------7--3-------7--3----------------------------|
A|3--------3---------3-5----------5----------------------------------|
E|-------------------------------------------------------------------|

   That?s Just about it. Not too hard. You can change it up by doing this:

     p   .5    p   .5      p   .5     p   .5
E|-------------------------------------------------------------------|
B|-------8---------8-----------10---------10-------------------------|
G|-------5---------5-----------7----------7--------------------------|
D|--5p2-------5p2---------7p3--------7p3-----------------------------|
A|3--------3---------3-5----------5----------------------------------|
E|-------------------------------------------------------------------|

    Whatever works for you. There are also other ways. You can use a hammer-off technique instead.
|p - Pull-off
|h - Hammer-on