Click the green flag, sit back, enjoy. Then change the sliders and repeat :) Some neat combos to start with: 1 & 5, 1 & 10, 20 & 5. Please check out the 800+ nice remixes made by other scratchers: https://scratch.mit.edu/studios/27457559/ And of course, feel free to remix yourself!
This started out as a simple remix, but turned into something very different. It could have had a lot less blocks of code, but I felt inclined to add a few extra things.