A few years back I was trying to learn to draw/paint crysanthemums.

Here is an image of how I practiced the sketch of the flower. I practiced quite a bit until I felt like I had a strong mental image and skill to project how the layers of petals and folding would work.

I realize this isn’t the kind of flowers you are doing but maybe my process will help you visualize how the flower petals fall.

I’ve used this for peonies. Similar structure to roses. It’s the same basic technique.