The Chinese idiom 东施效颦 (dong1 shi1 xiao4 pin2) literally means a ludicrous imitation of beauty. It comes from 《庄子·天运》 written by Zhuang Zhou in the Pre-Qin Period.
Long ago there lived a famous beauty, Xi Shi (西施). One day Xi Shi had a pain in her chest which caused her to hold her bosom and frown in pain. When an ugly woman (called Dong Shi (東施)) from the same village saw Xi Shi out walking, she took notice of Xi's behaviour. Like everyone in the village, Dong Shi knew that Xi Shi was the acme of beauty and so, in the hope of appearing to be more beautiful, she decided to imitate Xi Shi. Dong Shi put her hands on her bosom and knitted her eyebrows so that she was also frowning.
However, such an attempt was fundamentally flawed as the true reasons for Xi Shi's beauty went much deeper. In fact, rather than becoming more beautiful, Dong Shi simply made herself look even uglier. When others in the village saw Dong Shi behaving this way, they were horrified at how ugly she had become and everyone gave her a wide berth.
Today, Chinese people use the expression to describe people who are making a fool of themselves by trying to imitate behaviours that they do not really understand.
I have not been able to think of an English idiom with an equivalent meaning to this Chinese idiom - please let me know if you think you have one. However, it does remind me of something I once heard Charlie Munger (Warren Buffet's partner in Berkshire Hathaway) say:
If you mix raisins with turds, in the end you've still got turds.