How to make raod mesh for maps

I'm trying to make a map for BeamNG.Drive, but I really don't know how to make a road mesh. can someone tell me what program to use or how to do it?

 

In the world editor, select "Mesh Road Editor", and select the icon with a "+". and click on the terrain to make a road.

There's also "Decal Road Editor" to make a flat road that projects to the terrain.

 

the decal road editor helped, but when i use the mesh road editor, the road says no material

 

You need to select a material for the mesh road.

 

That worked!