Thank you for this insightful class! :)
When painting the leaves I tried following your steps, but also considered your reference pictures (which I screenshotted).

I noticed a number of things:
I tend to fiddle and detail even more as I'm layering colours. ^^; I really like the (very unrealistic) drops of yellow watercolor that cauliflowered in my lipstick leaf.
I had trouble defining the borders of the leaves without flat out outlining them or painting a background. Or doing really crisp edges and have everything look cartoony. *hm* (Any tips on that? I haven't really painted leaves before, especially not in this way.)
I am amazed by the different shapes and colours that leaves come in when you bother to actually study them!