- Download using the GitHub .zip download option and unzip them.
- Create the custom themes folder:
mkdir ~/Library/Developer/Xcode/UserData/FontAndColorThemes
- Move
Dark Castle.xccolortheme
file to this custom themes folder.
- In the menu bar:
Xcode -> Settings -> Themes
; - Select the Dark Castle theme;
- If you do not see it, you may need to restart
Xcode
; - Enjoy!