No need to outline your answer... you have got 30 minutes almost to attempt your answer.. writing in bullets may save your a lot of time.. as I attempt paper more in bullets form; that save me from unnecessary verbosity of full sentences.. it also makes the examiner feel at ease while going through your paper... just capture the central idea and give it in a bullet form..

For example,

if you give this heading

Causes of Poverty

Then your sub-heading let say include

"Low Literacy"

Then I think that's suffice. You need not write under this sub-heading that:

Low Literacy is a factor that causes poverty in Pakistan..

That's complete waste of time and also a kind of bugging the examiner.