Quill tools

 https://youtu.be/gBbKBAMNUy0

Start working on the grid and snap to it

Snap to Grid - left alt trigger and line tool - line snaps to grid

Duplicate - left alt trigger and grab

Import spherical image - https://youtu.be/gBbKBAMNUy0?t=378 1k x 1k gradient. png import and set to 360 equirectangular. Creates sphere. To scale select transform tool and select 'reset transform' the sphere jumps to the centre and snaps to grid. Then use gizmo to scale. The sphere then creates the perfect horizon line.

B Button - for colour picker

https://sketchfab.com/blogs/community/art-spotlight-naam-creating-art-oculus-quill/