I was an English major at University and beginning my essay was always the hardest part. Once I started writing it all seemed to fall into place. So my advice is to get a basic outline of what you want to argue, your position and your purpose of the paper...maybe gather some examples to back you up (quotes etc) and then just start wrting. Don't worry too much about making it pretty in the beginning...Just let the ideas pour out of you and keep writing. When you think you have something to work with....stop and start to pull it apart and divide it up.
The key is to just write. For me anyways. :) I hope that helps.
LEARN ENGLISH BY USING IT: ANSWERS & MOTIVATION FOR ANY ENGLISH LEARNER