Just press the green start flag. I suggest playing with the multipliers on radius and size, and the multiplier 1 that sets the turn angle "a", and the 2nd multiplier on the extra turn angle "b", and try different costumes.
Inspired by "The Art of John Edmark | Talk by Paul Dancstep | Exploratorium" https://www.youtube.com/watch?v=OFI1FJcGLeM Got the Golden Angle, 360/(phi^2), from https://www.princeton.edu/~akosmrlj/MAE545_S2017/lecture12_slides.pdf It's approximately 137.507765