You can watch the video or follow the step-by-step instructions below.
Start by importing Library.
The library sample includes dependencies required by other samples. Without it, the samples will not function.

Import one the game samples. Game or if you prefer addressables version, Game Addressables.
Luna UI Panel should open. If it didn't, open it via Tools > Cupkek Games > Luna UI Panel
Complete setup by clicking buttons.
Game adds demo scenes to Build Settings.
Game Addressables makes demo scenes addressable.

Go to Assets/Samples/LunaUI/ to find demo folder.
You can open and start the initialization scene.
Settings
Theme
Light
Contrast
Material
Dark
Dim
Material Dark
System
Sidebar(Light & Contrast only)
Font Family
DM Sans
Wix
Inclusive Sans
AR One Sans
Direction