It's fairly intuitive. Not that hard. Hotkeys: Q: Custom Color W: Eraser E: Color Picker A: Change Background S: Export Pixel Grid D: Import Pixel Grid
An idea I had at 2 AM. Have fun making pixel art in a slightly more convenient way than the scratch costume editor. No idea how you guys can share your creations because they would be limited to ~25 pixels because of the 500 character limit (the saving is NOT resource intensive)