Here is a small trick to plan and test the first version of your powerpoint presentation.
Open your favourite editor (Emacs?) and write the full slide deck here. Headings on new lines, bullet points indented by tabs. Move headings and correspondig bullet lists around to find the correct structure. When your are done, save the file with a "ppt" extension and open it in powerpoint. Voila! Now you have a starting point for your presentation