Parts

Different colors are helpful for displaying a complex assembly on your screen. If you assign different colors to the different parts, you and others are able to differentiate them better and get a much better impression of the design.

Workplanes

The same is true for workplanes. You could, for example, have your active workplane frame be green, workplane 1 if not active blue, workplane 2 pink, and so on. During a complex design phase, this can help you remember which workplane is located where.

Assign two different appearances to a workplane, either as a frame or as a full-colored plane.

Lines

Choose your own colors for geometry lines, construction lines, and the line or dot grid.