If you want you can play the B, Bm and C#m chords with an open high E string
i.e 

  B            C#m
|-0-|         |-0-|
|-4-|         |-5-|
|-4-|         |-6-|
|-4-|         |-6-|
|-2-|         |-4-|
|-x-|         |-x-|


Intro
E   B   C#m   Asus2
E   B   C#m   Asus2

E                   B  
 Can't believe your packin your bags
C#m             Asus2
  Tryin so hard not to cry
E                      B
 Had the best time and now its the worst time
C#m             Asus2
 But we have to say goodbye

B
 Don't promise that you're gonna write
       F#m
Though promise that you'll call
B                                      Asus2
 Just promise that you won't forget we had it all

               E            Bm
Cause you were mine for the Summer
       D               Asus2
Now we know its nearly over
           E          Bm
Feels like snow in September
      D              Asus2
But I always will remember
         E Bm       Asus2   E
You were my Summer love
                   E Bm       Asus2
You always will be my Summer love

E                   B   
 Wish that we could be alone now
C#m                    Asus2
 If we could find some place to hide
E                   B
 Make the last time just like the first time
C#m            Asus2
 Push a button and rewind

B
Don't say the word that's on your lips
      F#m
Don't look at me that way
B
 Just promise you'll remember
         Asus2
When the tide is grey

               E            Bm
Cause you were mine for the Summer
       D               Asus2
Now we know its nearly over
           E          Bm
Feels like snow in September
      D              Asus2
But I always will remember
         E Bm       Asus2   E
You were my Summer love
                   E Bm       Asus2
You always will be my Summer love

          B
So please don't make this any harder
   C#m
We can't take this any farther
    Asus2                              Asus2
And I know there's nothin that I wanna change, change


               E            Bm
Cause you were mine for the Summer
       D               Asus2
Now we know its nearly over
           E          Bm
Feels like snow in September
      D              Asus2
But I always will remember
         E Bm       Asus2   E
You were my Summer love
                   E Bm       Asus2  E
You always will be my Summer love
                   E Bm       Asus2  E
You always will be my Summer love
                   E Bm       Asus2
You always will be my Summer love