Remember the sectorization of the house with Bagua: the colour of the walls, the materials chosen for the floor, the choice of tiles… all this will depend on the sector in which the bathroom is located. For it to be feng shui, then the characteristics of the 5 Chinese elements must be respected.
The North, whose element is water, is the most favourable sector to plan a bathroom. There is no need to overdo it with the colour blue or black. Metal, which nourishes water, should be chosen (white, grey, etc.).
In the West and North-West, the metal element is needed, so grey or white colours, even gold or silver. You can feed it with earth (ceramic, sand, earthenware…).
If your shower room is to the east and south-east, you can put in as many green plants as possible, as these areas must be fed with the wood element.
In the North-East and South-East, the earth element is king. Why not decorate a bathroom with terracotta!
Finally, the South sector is a little more complicated to manage because Fire is the element that naturally conflicts with Water. Therefore, choose the most yin colours (mauve, powder pink) and not a flamboyant red. And take your baths by candlelight!