As is commonplace for all the high end phones of Xiaomi and in general the trend for many brands, the back cover is not removable, or rather it is not designed to be removed easily.
In some terminals though, the Mi4C is one of these, the back cover is so easy to disassemble that we can happily think of replacing it with one of a different color. In fact, this phone was marketed in 5 colors (white, black, yellow, light blue, pink) but if you bought it like me on “day one” you had to settle for white. It is time to remedy.
Before I go to the video tutorial, I make the usual and necessary premises: even if it is an "easy" operation, a minimum of dexterity and the right tools are required, otherwise you may face damages for which I am not responsible.
At the time of writing, this replacement is not present in the most well-known online stores, but I still track down a couple of Aliexpress sellers who already sell them. I will be happy to include your reports.
It is not guaranteed that the following products are original Xiaomi and above all the presence of the SIM trolley is not specified on both.