The design below was traced, then powdered pigment was rubbed onto the back of the tracing paper so I could transfer it onto paper I had burnished and then stained with washes of tea. It was painted with gouache, gilded and walnut ink was used to outline it.
It took a lot of practice to paint the fine lines without straying off course. Practice on sheets of paper with different inks and gouache below. Using thin brushes - 000. My hand kept shaking at first. So some very wobbly lines for a while.
Dreadful but not the worst I did!
The trick is to keep the brush at a 90 degree angle to the paper and paint very slowly so you have control. I ended up using magnifying glasses too. It's the kind of thing you need to paint often to get really good at. The designs get far bigger and much more complex than my final one, which is like a little baby step.
Rotational symmetry - painted with white ink
Sketchbook painting of blue tile