Zhang Baolan makes a peony out of cotton wool at her home in Yanta district, Xi'an city, Shaanxi province, March 20, 2017. [Photo/VCG]

Zhang's cotton wool drawing was listed as an intangible cultural heritage of Xi'an city in 2011. To help pass the skill down, Zhang has complied textbooks for teaching, and she teaches students in a school of special educational needs each week. So far, she has taught at least 200 apprentices in total.

The process of making cotton wool drawings is arduous and the long hours of toil have harmed her neck and eyes.

The first step is to select fine cotton wool. The breed Zhang uses is super grade cotton wool bought from pharmacy. Then dye the cotton wool in a hot pot and dry it in the sun.

When painting, first draw clear outlines of each part on a piece of paper and then paste the dyed cotton wool on the paper. The materials for each painting are cheap and easy to find, while the outcome is vivid and amazing.