I never got into coloringbooks. My vision was always based more on shapes and colors than lines, so outlines and fine details never did much for me.
Not that I didn't do a lot of drawing (and most certainly still would if my vision hadn't gotten too weak to do so). By which I probably mean coloring. Since I typically didn't bother with outlines, there was this tendency for things to wind up shaped not-quite-right... and hands and feet are simply out of the question (I hear those are hard for people with perfect vision... who outline things). (It was very rare that I bothered with faces, either; usually the most would be ey-dots).

In second grade, I had some markers that had different smells for the different colors, though I don't think this was intentional. The smells were pretty awful; red was something resembling beer, orange was like fish. Most of them weren't quite so distinct. That year, we actually put braille labels on the markers, but they wouldn't stay on.

A couple years ago, I bought some crayons, since I noticed I was having a bit more success with those nowadays. I tried to mark them with tiny cuts at different spots to distinguish the colors... but I've forgotten which was which already.