Before starting any research or secondary reading, it is important to establish your line of argument because this will help to direct your essay and make sure you answer the question.

A good tip would be: if you can't define your argument in one sentence then it isn't properly developed. 

Once you've got your argument done, pick your top three or four points (depending on the essay length) and write bullet points under each one of the sub points you will make in that paragraph. 

Once you've got your argument and paragraph plan, you can start gathering quotations and secondary sources to support your essay.