Modded Installation & Duplication
This guide is for the Steam version, if you're running the Microsoft Store or Gamepass version, see here.
Duplicating your Starbound installation is recommended so your existing vanilla characters and planets are not affected. If you don't care about corrupting these existing planets or characters on vanilla servers, skip to step 6.
1: Open Steam library and right click Starbound, then click properties.
2: Click LOCAL FILES and then Browse...
3: File explorer should open up to the root directory of your Starbound installation. Go up one directory and you should see all your Steam games. Duplicate your Starbound directory anywhere by copying and pasting.
4: In this case, the same default directory Steam uses.
5: Open up this duplicated Starbound directory and remove the storage directory if it exists.
6: Download and save the FrackinUniverse.pak file to your mods directory (See path).
7: Open the win64 directory (See path), and create a shortcut to your desktop. Use this shortcut on your desktop to easily launch the game.
Enjoy FU Starbound!