This is an amazing song by some amazing artists but
before we start, this is my first tab so bare with me. I 
enjoy finger picking most things so this is just the way 
I play the song. If you find that strumming works better 
for you than go for it, I'm no musical genius either so 
I will place the chord names I find from the "Jguitar.com 
Chord Namer" above the picking so you can have a better 
visualization of the timing.

D#M9                       A#m#5add5               D#M9
l---------------------------------------------------------------------------l
l-----------6-----------------------6-----------------------6--------7s6----l
l--------6-----6-----------------6-----6-----------------6-----6------------l
l-----4-----------4-----4-----4-----------4-----------4-----------4---------l
l--6-----------------6-----------------------0--4--6------------------------l
l--------------------------6------------------------------------------------l 
   
  A#m#5add5              Dsus4#5                  A7b9sus4
l-----------------------------------2------------------------2--------------l
l-----------6--------------------2-----2------------------2-----2-----------l
l--------6-----6--------------2-----------2-----2------2-----------2--------l
l-----4-----------4---------------------------------------------------------l
l--------------------0--4--5-----------------5------------------------------l
l--6-----------------------------------------------5------------------2s5s2-l

G#7sus2
l---------------------------------------------------------------------------l
l---------------------------------------------------------------------------l
l--------3--4p3-----------------3--4p3--------------------------------------l
l-----4----------4-----4-----4----------4-----4-----------------------------l
l------------------------------------------------0--4-----------------------l
l--4----------------4-----4----------------4--------------------------------l 
  This is the entire song but I play it twice like this 
as an intro before I start the vocals.

Also, because this is the only part to the song 
I like to make some variation with the feel of the
guitar between the intro and verses. I will do my 
best to display how I play the verses 
as well as place the lyrics in the right place. 
  
The * is an indication of where you slap the strings 
to give it somewhat of a snare hit sound.

*                    *                 *                   *
l------------------------------------------------------------------------l
l-----------6-----------------6----------------6-------7s6~---------6----l
l--------6-----------------6----------------6----------6~--------6-------l
l-----4-----------------4----------------4-------------4~-----4----------l 
l--6-------------------------------0-4-6------------6--------------------l
l--------------------6--------------------------------------6------------l
[Verse 1]      How does it measure up?               Was I good enough?
               And if it's meant to be               What will it mean to me     
[Chorus] x2    Always              Headstrong        Calling            Me home
[Verse 2]      And as I fill my cup                  Wonder how I had enough
               What will be will be                  Not without some mystery
        
                                 *                                          *
l-------------2------2~----------2------------------------------------------l
l----------2---------2~-------2---------------------------------------------l
l-------2------------2~----2-------------------3-4p3-----------3-4p3--------l
l--------------------------------------------4-------4---4---4--------------l
l0-4-5------------5---------------------------------------------------------l
l-----------------------5-----------5-5s7s4------------4---4---------4------l
                               I may never   know.
                            I never want to know.
                There  was aplace (x02210@1)I belonged.
                               and I'm not sure.
                               of that, I'm sure.

Intro x2
Verse
Intro x2
Chorus
Intro x2
Verse 
Chorus
Outro

There you have it, I probably made it harder than I should 
have but the thing that will make a big difference 
is actually listening to the song and playing along just to 
get the feel that YOU want with everything. 
Anyway, thanks and I hope you find this to be useful.