Page layout and map scale

(Rhino 5, Windows 10)

I am trying to draw a large geological map on a A3 or A1 paper size. For that I need to setup paper size and also setup a scale, like, 1:200 or 1:500. But I couldn’t find it. Can someone help me? I am waiting for some suggestion for page setup and scale.

Thanks in advance.

Set up the Layout itself to be printed at 1:1.
Set the display scale in the Details to 1:200 or 1:500 as needed.
Here’s a link to a tutorial: