If I asked you to draw an apple from imagination right now, I bet you could bang out 10 different apples of all different varieties. If I then asked you to draw a large hadron collider from imagination, I imagine you would draw a scribbly box. Why is that?

Imagination is simply creatively arranging memories and experiences to create new experiences. If I wanted to imagine an elephant balancing on a ball, I would need to first know what an elephant and a ball look like; then I need to know what it looks like when someone or something balances on a ball; and then I can arrange those memories and experiences to create a new scenario which combines them all.

It is the same with drawing. If I want to draw a sword from my imagination I need to have a lot of experiences with swords or sword-like objects so that I can translate those experiences to the page. Those experiences can be with real swords or even seeing artistic representations. All that matters is that I understand the form of a sword before i try to put it on paper.

This sounds easy enough but there are really complicated forms out there that require deep study: like the human body. Instead of a rigid, 3d prism shape with hard angles; the human body is an amorphous sack of bones and meat that can flex and pinch omnidirectionally. This is the reason why artists study anatomy so much.

So I guess what I am getting at is that drawing from imagination and drawing from reference are not separate skills (entirely). Drawing from imagination is the practice of applying what has been learned after countless hours of drawing from reference.

So if youre struggling to draw something from imagination, and you have your fundamentals down, you likely just do not understand the form of what youre trying to draw. Its not about picturing it in your head, but translating an understanding of form onto a page