Using the Rust builder: (suggested)

Setup:

Make sure you can launch vscode extensions: https://code.visualstudio.com/api/extension-guides/color-theme#create-a-new-color-theme
Make sure you can build and run Rust programs: https://www.rust-lang.org/tools/install

Develop:

1: In the 'builder' folder, run 'cargo run' (or just run 'cargo -C ./builder -Z unstable-options run' from the main folder)
2: Make changes to 'src color-theme.json', and the actual theme files will automatically be updated
3: When done, enter 'Stop' (or 's') to stop the builder

Export:

1: In the 'builder' folder, run 'cargo run'
2: Enter 'Export', and a folder named 'output' should appear with the finished extension (this command does not update the theme files, because the builder already builds the themes every time it is started)

Using the Node builder: (OUTDATED)

Setup:

Make sure you can launch vscode extensions: https://code.visualstudio.com/api/extension-guides/color-theme#create-a-new-color-theme
Install 'hjson' and 'fs-extras' through npm
Every time you use the builders, make sure you're in the /builder folder

Develop:

1: Make changes to 'src color-theme.json'
2: Run 'node build_themes.js' to create and/or update the actual theme files
3: Repeat

Export:

Run 'node build_extension.js', and a folder named 'output' should appear with the finished extension (this script also builds the themes)