It is useful to use the worldbuilder to create a map that includes the same bonuses/terrain as the screenshot. The exact shape of the terrain, is, I think, less important. It is also useful to generate a number of maps, just to get a notion of what this particular kind of map looks like.
Usually someone will produce and post in the pre-game tread a map that is an exact likeness of what we can see from the screen shot. You can download those maps, if you like.
I generally create my own practice game, making sure the the tiles included on the map have the same bonuses/terrain as the screen shot, but do not go to the extra effort of bending the terrain into the exact shape shown in the screen shot.
The important thing for me, is to generate a reasonable opening (a la chess) and get a flavor of how the map will play, i. e., how Barbs are, how the AI's do on this map, when the wonders get done and religions are founded, etc.