If you do not have any article or books about your chosen subject you can look initially in a good encyclopaedia. That usually gives a result. If you can define the subject properly then you may ask for help in the library. Someone will help you to do a search in the catalogue usually resulting in you leaving with some books; newspaper articles or even a video or CD-ROM. You can also consult the Internet, at home, at school or in the library.
First read all the information you gathered thoroughly. On a piece of paper note down in rough all the information you find important and you want to deal with. That way you can choose the most important points that you wish to include. Think carefully about the order in which you plan to deal with the various points. Write down the order on a piece of paper and see if it is logical. Could someone else easily understand it? In doing so you have already worked out an initial order of the chapters.
It is important that you keep a list of all the titles of books and articles that you have used during your preparations. You can use this list in your conclusion. That way the reader can see how much research you have done.