Dear Andrea_73,
If you have the Genius Mind course, there is a good "Visually Thinking" pamphlet in that course.
Instead of visualizing, use your strongersense. for example, you may be more tactile/kinesthetic and easily feel things.Feel the sensation what what is happening when doing what Chunyi is asking you to see. You may be more auditory - then follow along with the instructions, knowing that it is happening, what sound would/is it making?
As Master Lin says at times - If you are finding it difficult to visualize it, then imagine it. If you are having difficulty imagining it, pretend it's there.
Much Love,
Shawn