I am making a large-map game, how do I make the lighting cost as little as posssible?

I am trying to make a game with a large map. I don’t really know how to use the lightmassimportancevolume, and other lighting things effectively. All I really have experience in is blueprints and placing actors in the world. Whenever i build the lighting, the game gets really laggy, or it doesn’t because it says I need to restrict the bounds of a lightmass importance volume, when I haven’t even added one in yet.

(p.s. how do I use the geometry editing tool to change the shapes of actors, I think it would be really god to know how to use so that i can make the shapes into diffferent ones)

The lowest cost level is one without lighting… but there are only so many games that can get away with that.
the main things that drive up the cost of lighting is overlapping lights, lights that are movable are more expensive than static lighting, and having a large attenuation radius on point and spot lights.

Also you don’t want to have more than one directional light generally.

Lightmass Imprt Vol