Dear Irsa sister,
The best way to pass the Essay paper is to get rid of the fear of this paper. It is an easy paper if you follow two of my advices.Firstly there is no need to prepare for the essay just keep on preparing for Current Affairs by reading Dawn and Imtiaz Shahid's Contemporary Affairs. Secondly Write as much as you can on different topics. Make writing on different topics your habbit, daily pick up any topic even you are allowed to write about the things you did throughout the day. Follow these advices for few months and you will InshaAllah find that you are ready for Essay. Please dont listen to those who says Essay is very difficult to pass. Just keep on working and IshaAllah you will get success.
Duaon main yaad rakhiye ga, Allah karey sub log pass hojayien. Sub kay result kay liye dua karein.

Allah Hafiz,
NCH