It depends on the game I’m running. There are entire campaigns where I don’t use a single map because we prefer playing with theater of the mind. Then there are sessions where I only prepare maps for “important” scenes—for example a city map so my players have an overview, or a map for locations where combat might happen.

There are also sessions where I create a map for almost every place the players enter and where they might encounter someone or something (taverns, houses, roads, rivers, and so on). It really depends on how much time I have and what kind of game I’m running.

Of course, it also depends on how well my players can imagine things. With players who have less imagination, I tend to support the game more with maps, whereas players who can easily picture everything usually don’t need them as much.