Capo I or IV (they actually play it on Iv but I find it easier to sing with the capo on 
the first fret)

(single strumming)
          G5
Should've kissed you there
            D5
I should've held your face
            E5
I should've watched those eyes
           C5
Instead of run in place
            G5
I should've called you out
            D5
I should've said your name
            E5
I should've turned around
            C5
I should've looked again

 Chorus :
    D5   E5                 C5      G5      G5
But oh, I'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
       D5         E5                  C5       G5
As you turn, you take your heart and walk away


(strumming)
          G5
Should've held my ground
           D5
I could've been redeemed
          E5
For every second chance
                C5
That changed its mind on me
            G5
I should've spoken up
            D5
I should've proudly claimed
           E5
That oh my head's to blame
         C5
For all my heart's mistakes

 Chorus :

    D5   E5                 C5      G5      G5
But oh, I'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
       D5         E5                  C5       G5
As you turn, you take your heart and walk away

    G5     D5       E5    C5
And it's you, and it's you
    G5     D5       E5    C5
And it's you, and it's you
         G5       D5            E5    C5
And it's falling down, as you walk away
         G5      D5          E5  D5
And it's on me now, as you go

 Chorus :
    D5   E5                 C5      G5      G5
But oh, I'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
       D5         E5                  C5       G5
As you turn, you take your heart and walk away


         G5       D5            E5    C5
And it's falling down, as you walk away
         G5      D5          E5  D5
And it's on me now, as you go


 Chorus :
    D5   E5                 C5      G5      G5
But oh, I'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
E5                  C5      G5
I 'm staring at the mess I made
       D5         E5                  C5
As you turn, you take your heart and walk away