If you are writing a research paper for a class, consider the other students. Is it likely that they will also be writing about your topic? How can you keep your paper unique and interesting if everyone is writing about the same thing?
Whenever possible, choose a topic that you feel passionate about. Writing about something you enjoy certainly shows in the final product, making it more likely that you will be successful writing a paper about something you enjoy.
Now that you have carefully worked through your evidence, write a conclusion that briefly summarizes your findings for the reader and provides a sense of closure. Start by briefly restating the thesis statement, then remind the reader of the points you covered over the course of the paper. Slowly zoom out of the topic as you write, ending on a broad note by emphasizing the larger implication of your findings.
Although it may seem counter-intuitive, writing your introduction first may be more difficult to accomplish than starting with the meat of your paper. Starting by writing the main points (focusing on supporting your thesis) allows you to slightly change and manipulate your ideas and commentary.