How to write a good paper
Just as giving a good talk is difficult and has to be learned, so writing a good paper is challenging as well. Presenting your ideas on paper is something that even grown-up scientists sometimes struggle with. A seminar is an opportunity for training to write a paper, and for getting feedback on it.
Writing a seminar paper is a somewhat unnatural task: A research paper is about presenting your ideas, but you're really presenting someone else's ideas. To help you along with this, I am asking you to come up with one thought of your own and put that into the paper. The idea is to write the paper as if the content were your own (while giving due credit to the true authors, of course). I also urge you to start writing your paper well before the deadline: You will probably need more time than you anticipate. If at any time you want to talk about your paper, come see me.
Here is some general advice on writing good research papers that you may want to read.