Oftentimes, I need to visualize something in order to properly understand a problem to solve it. This kind of visualization may involve drawing lines, circles, triangles, rectangles, polygons etc.
I know many people use either red, blue or green colors for this. But perhaps you have favorite colors that you use? What set of colors you typically use for drawing?
I personally like Color.cornflower/Color.steelblue in combination with Color.orange or Color.orangered.

Color.tomato is also an interesting alternative to Color.orange.