How can i make an interesting selection UI?

Hey! so, ive reached a step where i need to learn UI design and make asthetically pleasing and/or useful UIs, i tried to learn how to use the golden ratio, but i couldn’t see literally any true use for it, as a 1.618 ratio for sidebar to view area is horrible, literally all i could get a use out of it is making lineheight 1.618
now for what i want, i want to be able to design compelling UI and UX for my class selection and editing screen, it’s not something truly complex, all i want it to be able to do is:

  • have a window where all the abilities of the class is displayed, and buttons around it that you can use to swap abilities
  • Have a smaller window showing a simple description of the class, like it’s properties and target playstyle
  • a sidebar where you can select the class you want to use and edit
  • floating boxes you can use to select the class’ accessories or morph skin
  • and if possible, a slider that you can use to rotate the model to see it’s model in 360

im mostly a scripter, so i just need help with the UI and UX side
i have no idea how much of it is actually possible, but if someone has any suggestion that helps me design it, please tell me!

General UI design help also works btw