Hi everyone! 
These are the correct chords as Jamie McDell herself tweeted the chord progression - all I did was figure out where in the lyrics the chords change over.
No capo, standard tuning. 
I like to play this slightly slowed down using fingerstyle, but this is not how Jamie plays it.
Hope you like this tab!!

~~~

            
I'm heading do

            
wn this road,
             
I might not kn

              
ow which way t

  
o go
            
That's OK, I'm

             
 just young &a

 
mp; dumb!
            
I wear my shoe

         
s a little big

ger,
             
I fall for all

        
 your dirty tr

icks
            
It's fine, I'm

             
 just young &a

 
mp; dumb!

   
            
Missy, come an

           
d catch me if 

you can
             
And wrap me 'r

              
ound your hips

      
 and let's jus

t dance
             
Missed in shoo

              
ting an arrow 

   
through my hea

rt
             
Come on, let's

            
 take this way

 
 too far


            
I get away wit

    
h anything
             
I'll rob your 

             
heart with jus

              
t a wink and r

       
un
             
I'm just young

    
 & dumb!


          
Run me off thi

   
s road,
             
Crash right of

f the bridge
             
We only got on

   
e life to live

!
          
Before we get 

    
too old,
             
Take your memo

             
ries, they're 

              
all that you'l

       
l have left of

 me

          
Da da da da da

 da da

Da da da da da

 da da
          
Da da da da da

 da da
           
Da da da da da


 da da


 I'm putting on this show
 Forgetting what I should have known
 I beat my drums, 'cause I'm young & dumb!
 I'm shooting cannonball, exploding everywhere I fall
 You better run, 'cause I'm young & dumb!

 Missy, come and catch me if you can
 And wrap me 'round your hips and let's just dance
 Missed in shooting an arrow through my heart
 Come on, let's take this way too far

 I'm standing with a gun
 I'm counting down four, three, two, one
 Tick-tock it's time, I'm just young & dumb!

 Run me off this road,
 Crash right off the bridge
 We only got one life to live!
 Before we get too old,
 Take your memories, they're all that you'll have left of me
 Running off this road,
 Don't you rescue me,
 I know your water's testing me
 Cross my way back home,
 But it's all fun to me,
 'cause walls are my worst enemy!

 Da ta ta ta ta ta
 Da ta ta ta ta ta
 Da ta ta ta ta ta
 Da ta ta ta ta ta

 Now there's blisters on my feet,
 Giant hole inside my dreams,
 All for some fun, I was young & dumb!