Again, the methodology of your work should be in strong accordance with the initial thesis and the main aim of your research. Visit the university library - the librarians might be eager to provide you with a good textbook as well as with a recommendation on how to start a cover letter . Thus, a lot of books can teach you research philosophy, so that you will be able to choose methods on your own. Moreover, it is convenient to look for someone else's thesis methodology example in the library. Remember, only deep theoretical knowledge can help you to reinforce your dissertation with firm methodological underpinnings.