cheers!
that only half makes sense to me, but I’m sure in another couple weeks it will be clear
Build your commercial districts next to rivers, construction disctrics next to mined resources, campus districts next to rainforest or mountains. Some districts will give adjacency bonuses when placed next to other districts. Try to build all available buildings in one district before building a new one as the increased bonuses are worth it. This is why it is a good idea to have different districts in different cities as well as the different terrain adjacency bonuses.