Triangulation is one test for improving the validity and reliability of research or evaluation of findings. As the name implies, triangulation is a strategy that controls bias and helps to establish valid conclusions because it uses at least three (thus, the "tri-" prefix) different types of methods or tools to collect data from which conclusions are made. Many researchers argue that triangulation strengthens a study by combining methods. This can mean using several kinds of methods or data, including using both quantitative and qualitative approaches. By using at least three different methods, the researcher is about to obtain multiple, diverse perceptions of a single concept.
Of course your preparation will involve a detailed plan or outline and this can take up a number of pages. Not only would you list all the main points to discuss about your PhD thesis but there will also be a variety of minor points related to or supporting each major point. The greater the detail of your plan, the more likely you are to write like a professional paper writer. But then too there is the issue of your equipment and timetable. Both have a major impact on your ability to write well. Make sure that you have the right writing equipment and that you have a detailed timetable with goals or milestones clearly listed.