I've started practicing drawing without any reference. It makes sense it's the next step. It feels like a practice in visualizing. It's scary at first... feels a bit like being naked in public. But I've realized it becomes a practice of trusting yourself. Trusting that I've seen these things millions of times throughout my life, and I do know what they look like. I know what a person standing, sitting, walking or running looks like. I know what an outstretched arm looks like. So I close my eyes for a bit... or maybe I don't and still see the visualization anyway... then start drawing it. And i'm amazed how accurate they come out. The big one is a few people interacting, each layered in multiple positions. Fun!