This webpage has resources that provide models and guidelines for creating narratives about the topic you choose.
Here is a very helpful video about doing presentations, including best practices for using Powerpoint as well as presentation techniques.
Creating Effective Presentations (materials assembled by Lehigh LIbrary and Technology Services staff members Jarret Brown and Holly Zakos ).
It's a good idea to add the sources you used to the final slide of your presentation Powerpoint. And/or you can add citations at the bottom of individual slides.
You not only need to know the science behind a particular geological phenomenon well, but you also have to be able to explain it in an engaging, understandable way to an audience of non-scientists! Below are ways to approach this task from a storytelling perspective.
NOAA has a variety of presentations that can serve as models while you develop your presentation scripts with corresponding images.