More Worldmaps!

I'm embarassed to admit that I just want to world-build and here I am, back at the quick and dirty end of things, which is bunch of boxes, essentially a schematic mapped to a rectangular world map. What I can do is rough out the land and sea area, simple hydrographic ratio, although this should be a height map paired with an inventory of water.
The square represents an octahedron; the corners fold down to represent the lower, far, hemisphere and the inner square represents the upper, near, hemisphere. Likewise the four diagonal squares also represent an octahedron, the sideways cross folds into a cube, and the five rectangles or ten squares, twenty triangles, fold into an icosahedron, a d20 in gamer speak.

Collaborative World Building Game or Activity

Based on how much I love world-building and hate or resent 'Raised By Wolves', I would like to run a collaborative world-building game or activity. I am not sure that 'Game' is the right word. This is a structured version of my usual zeroth session of a role playing campaign.

Usually I would get together with a couple of players and we would hash out what we want, although I guess I ran an awful of space adventure games, have starship, will travel for fun and mayhem.