I figured this out by watching a live acoustic version, so it should be pretty accurate.
You'll have to figure out the timing and the strumming on your own.

Acoustic Video Link: http://bit.ly/hzOfW2

Chords:
A5- x42200, x022xx
B5- x244xx
C#5- x466xx
D- xx0232
D5- x577xx
E- 022100, x799xx
F#5- 244xxx

Intro:

F#5 (244xxx@1)Verse 1:

F#5 (244xxx@1)Take a breath, easy now
My eyes are playing tricks on me
C#5 (x133xx@4)                        E(022100) (022100@1) Tell me the mirror must be lying
It's not what I wanna see
F#5 (244xxx@1)How can I just be me
                           C#5When (x133xx@4)I don't recognize myself
                          E(022100) (022100@1)Wishing I was something better
I wanna be someone else

Refrain:

D (xx0232@1)    B5 (x244xx@1)      F#5 (244xxx@1)              A5(x42200) (x022xx@1)Lately I've been fighting, with that girl in the mirror
D (xx0232@1)   B5 (x244xx@1)         F#5 (244xxx@1)       A5(x022xx) (x022xx@1) 
Who decides what's beautiful?
D (xx0232@1)    B5 (x244xx@1)   F#5 (244xxx@1)         A5(x42200) (x022xx@1)We are all so different, not one is the same
D (xx0232@1)                             B5Now (x244xx@1)it's time that we can all decide
(Pause)            F#5What's (244xxx@1)beautiful,     whoa

Verse 2:

F#5 (244xxx@1)Look at her, so confident
Perfection, so appealing
C#5 (x133xx@4)                         E(022100) (022100@1) She seems so happy but she's plastic
Is that what I wanna be?
F#5 (244xxx@1)I deal with this everyday
                             C#5I'm (x133xx@4)slowly starting to break free.
                      E(022100) (022100@1)Learning how to truly love who I was made to be
Who I was made to be

Refrain:

D (xx0232@1)    B5 (x244xx@1)      F#5 (244xxx@1)              A5(x42200) (x022xx@1)Lately I've been fighting, with that girl in the mirror
D (xx0232@1)   B5 (x244xx@1)         F#5 (244xxx@1)       A5(x022xx) (x022xx@1) 
Who decides what's beautiful?
D (xx0232@1)    B5 (x244xx@1)   F#5 (244xxx@1)         A5(x42200) (x022xx@1)We are all so different, not one is the same
D (xx0232@1)                             B5Now (x244xx@1)it's time that we can all decide
(Pause)            F#5What's (244xxx@1)beautiful
What's beautiful

Bridge:

B5 (x244xx@1)               C#5I've (x133xx@4)had enough to see what's fake
D5 (xx023x@1)         E(x799xx) (022100@1)       F#5 (244xxx@1)It's always been my choice to make
B5 (x244xx@1)      C#5 (x133xx@4) D5 (xx023x@1)Imaginary enemy,
          E(x799xx) (022100@1)    F#5No (244xxx@1)longer has control of me

F#5 
We all define what's beautiful
A5(x022xx) (x022xx@1)      B5 (x244xx@1)        A5(x022xx) (x022xx@1)We all define, we will decide
F#5We (244xxx@1)all define what's beautiful
A5(x022xx) (x022xx@1)      B5We (x244xx@1)all define, we will decide

Refrain:

F#5 (244xxx@1)            A5(x42200) (x022xx@1)Lately I've been fighting, with that girl in the mirror
D (xx0232@1)                B5Who (x244xx@1)decides what's beautiful?
             
              D (xx0232@1)B5 (x244xx@1)F#5 (244xxx@1)A5(x42200) (x022xx@1)D (xx0232@1)  B5 (x244xx@1)F#5 (244xxx@1) A5(x022xx) (x022xx@1)What's beautiful          Ohhh,       yeah

Refrain:

D (xx0232@1)    B5 (x244xx@1)      F#5 (244xxx@1)              A5(x42200) (x022xx@1)Lately I've been fighting, with that girl in the mirror
D (xx0232@1)   B5 (x244xx@1)         F#5 (244xxx@1)       A5(x022xx) (x022xx@1) 
Who decides what's beautiful?
D (xx0232@1)    B5 (x244xx@1)   F#5 (244xxx@1)         A5(x42200) (x022xx@1)We are all so different, not one is the same
D (xx0232@1)                             B5Now (x244xx@1)it's time that we can all decide
(Pause)            F#5 (play it through until end)
What's beautiful
What's beautiful
What's beautiful