Make a "mirror" (first step)
  1. Open GitHub (if you don't have an account, make one 🤷)
  2. Get a domain, or skip if you're using your GitHub username.
    To get a domain: visit FreeDNS, register a domain, and point the IP to 185.199.108.153.
  3. Fork a repository (e.g.:
    Scratch: scratch-gui
    Turbowarp: scratch-gui
    PenguinMod: penguinmod.github.io
    Snail IDE: snail-ide.github.io)
    If you're using your GitHub username as a domain, name the repo yourusername.github.io.
  4. Go to the "Actions" tab and start the node.js.yml workflow.
  5. You're done! Visit your GitHub Pages site 🎉

Custom domain: If using a FreeDNS/custom domain, go to Settings > Pages and set the custom domain field.

Change colors
  1. Open colors.css and find a color picker (like from Google).
  2. Most colors are in HSL format. Pick your color and copy the HSL value.
  3. Paste the HSL value into the appropriate place, removing the degree symbol.
  4. You're done!

Note: Don't change the last value (alpha) in values like hsl(70, 50%, 80%, 50%).

Also avoid changing essential variables like white-ui.

For making a mod of PenguinMod, Snail IDE
  1. Find the file containing unhelpfultip.
  2. Copy and paste an entry, then replace the content in the quotation marks.
  3. Add your own tip. You can delete the ones you don't want.
For advanced CSS customization

Edit components/gui/gui.css to change specific UI components.

Example: On merrctaft's mod, I changed the tabs using CSS.