What’s your approach to inter-cellular diagrams?

I am working on an illustration that details the interactions between platelet activation/the coagulation cascade & the immune system (dubbed “thrombo-inflammation”). I usually illustrate gross anatomy and do this is a new venture for me. What’s your process to complicated processes like the ones you see in immune cell interactions and activations? How do I organize it in a way that tells a story and makes sense to the reader?