An EE is an authentic piece of work following the research process. Once you have chosen your RQ, you should:
Undertake lots of preliminary reading on your chosen topic
Gather as much evidence as possible from reliable and relevant secondary sources to begin to answer your working research question. You might need to refine the question as you continue to read.
Analyse the information you have gathered so far to determine:
To what extent is the information from the various sources consistent?
What additional information do I need to answer my question?
Continue to collect the information you need by primary or further secondary research
Write your Introduction - but remember, you will probably want to go back and change that towards the end of the EE process
And then - you begin to construct the body of your essay, which should be presented in the form of a reasoned argument.
Compare/contrast the evidence collected from secondary sources with each other or with your findings from the primary research and formulate a conclusion that answers your research question.