It sounds best if you play a bassline before every G-Chord like:
E - F# - G (Chord)

G Em 2x

G             Em              G
They say the grass is always greener
         Em                D
But they wouldn't if they meet her
   
'cause she's got a way of
  C            D     G
turning everything around


            Em                G
I see her through the big end of
       Em                  D
a telescope although she seems so far away
              C
I still have hope that maybe
                   D
someday we'll be close


           G      D         C      D
And she's got me thinking upside down
G        D                C                D
Talking backward out the wrong side of my mouth
G       D            C        D
Making promises that I can't keep
              C       D
That's how I know

That I'm in deep

G Em 2x

G             Em             G
All signs say stop but I say go
             Em           D
The light is red but even so

I won't slow down until we
C                D
find some common ground

G           Em          G
There is no time to hesitate
             Em             D
'cause if I do she'll slip away
                                 C
And then the hour will grow too late
                         D
For me to tell her how I feel

        G      D         C      D
And she's got me thinking upside down
G        D                C                D
Talking backward out the wrong side of my mouth
G       D            C        D
Making promises that I can't keep
              C         D
That's how I know

That I'm in deep

G Em 2x

     ! (sorry it's gonna take time to work out the chords of the bridge)

There's something about her that just glows

In the sun and rain and deepest winter snow


           G      D         C      D
And she's got me thinking upside down
G        D                C                D
Talking backward out the wrong side of my mouth
G       D            C        D
Making promises that I can't keep
              C      D
That's how I know

           G      D         C      D
And she's got me thinking upside down
G        D                C                D
Talking backward out the wrong side of my mouth
G       D            C        D
Making promises that I can't keep
              C      D
That's how I know
              C      D
That's how I know
              C      D
That's how I know

That I'm in deep

G Em 2x
G