I tabbed it out and found it very hard to sing and play at the same time. 
So this is a simplified version. 
Feel free to add the original melody in your own interpretation ;)


Am         Bm
This sunny Sunday
     Am          Bm
Is a good day to go
Am                    Bm
Guess you want me to stay
                 Am      C   Bm
Well then let me know
      Am        
And I hate to say
            C        Bm
It's been a waste of time
  Am                    C      Bm    Bm
I hate to interrupt the flow

[Chorus]

Am Am/C Am Am/C   Am Am/C Am Am/C