Sid Meier's Civilization VI

• A single luxury resource gives 4 amenities that get divided up among your cities with the amenities going to whichever city needs it most. Multiple copes of a luxury resource don't normally give any more amenities and should be traded away.

• Gold is highly useful, make sure to not neglect Harbors/Commercial Districts too much early on as they're the primary method of acquiring new Trade Routes for bringing in wealth and growing your new cities.

• Plan ahead with your district positions by checking the adjacency bonuses they get. A common example is placing a Campus and/or Holy Site on a tile surrounded by mountains, or a Harbor near coastal resources. Adjacencies also work between different cities, for example districts from two different cities can get a bonus from each other.

• Certain district buildings, primarily those from the Industrial and Entertainment districts, also provide (by default) a non-stacking bonus to cities within a 6-tile radius which can make those districts more useful when placed near multiple cities than in the outskirts.

• Don't forget about the ability to harvest features such as forests and bonus resources with Builders. For example plonking a district on a forest tile simply removes the forest without yielding anything, so it's always preferable to first use a Builder to remove the forest for the big one-time boost and then start district construction there.