After looking for a tab for this song, i realised that none of the tabs are correct. 
This is how i play it and it sounds right to me.
I give credit to
http://tabs.ultimate-guitar.com/w/wiz_khalifa/young_wild_and_free_tab.htm
for parts of my tab.

Basically, all you have to do is repeat the same thing over and over again.

e|-------------------|
B|-7-5-3---3-3-3-----|
G|-------4-----------|  x4
D|-------------------|
A|-------------------|
E|-------------------|
So what we get drunk
So what we smoke weed
We're just having fun
We don't care who sees
e|-------------------|
B|-7-5-3---3-3-3-----|
G|-------4-----------|  x2
D|-------------------|
A|-------------------|
E|-------------------|
So what we go out
That's how its supposed to be
e|----------3-3-3----------------|
B|-7-5-3-----------7-5-3---3-3-3-|
G|-------4---------------4-------|
D|-------------------------------|
A|-------------------------------|
E|-------------------------------|
Living young and wild and free

Sometimes i play the 7th(different) part:
e|---------3-3-3-|
B|-7-5-3---3-3-3-|
G|-------4-------|
D|---------------|
A|---------------|
E|---------------|

They both work.