The introduction is, in many respects, the conclusion written in reverse: start by generally introducing the larger topic, then orient the reader in the area you’ve focused on, and finally, supply the thesis statement. Avoid repeating exact phrases that you already used in the conclusion.
Once you’ve gathered all your research, print it out (if it is an online source) and gather post-its or anything you need to mark notes in the books/magazines you are using. This step is very important: read through your research, take notes on what you think is important, and highlight key facts and phrases. Write directly on copies you’ve made, or use slips of paper tucked into pages to mark places of importance.
Any information that doesn’t fit within the framework of your outline, and doesn’t directly support your thesis statement, no matter how interesting, doesn’t belong in your research paper. Keep your focus narrow and avoid the kitchen sink approach. (You know, the one where you throw in every bit of interesting research you uncovered, including the fungal growth in the U-joint of your kitchen sink?) Everything you learn may be fascinating, but not all of it is going to be relevant to your paper.
Depending on your paper rubric, class guidelines, or formatting guidelines, you may have to organize your paper in a specific way. For example, when writing in APA format you must organize your paper by headings including the introduction, methods, results, and discussion. These guidelines will alter the way you craft your outline and final paper.