Half square triangles were step 1.
And lots of them:
The I needed to make the quarter square triangles for the pinwheel, I managed to get all the points quite good thankfully!
At this point I thought about fussy cutting the stripes so they could all point outwards and highlight the block, but I decided not to, and I am pleased. I feel like the stripes represent the wind blowing outwards from the pinwheel in all four directions.
My pinwheel center point wasn't great but if you aren't looking up close it looks like a nice pinwheel:
Overall I am very happy with this block, my scrappy colors are working out well.