Click the green flag, sit back, enjoy. Please check out the nice remixes made by other scratchers: https://scratch.mit.edu/studios/27457559/ And of course, feel free to remix yourself!
After seeing some remixes make good use of the 'change size' block, I wanted to give that a try myself. Tip: there are many more interesting patterns. Change the number in the 'turn 89' block and see what happens!