Try writing your body paragraphs first. Its hard to introduce someone you havent met, and it is equally difficult to introduce a paper you havent written. Write your body, go back and write a catchy opening (As the other answer says, answer a question or grab the attention of your reader), write a thesis, and then connect the opening and thesis. Afterwards, decide the main point or message of your essay and write about it in your conclusion (make sure to summarize the paper without bringing in any new information).
