Press the green flag to begin, then the cat will change colour and follow the mouse. If you press the spacebar the cat will clone itself and that will start changing colour. Press the up key to make the twirl effect and the bottom key to reset. Press the left key to pixelate the cat and the right to reset.
I got the colourful idea from the introduction video. The rest is original. Please note. Too many clones will cause it to lag.