It's too general/abstract. Instead of a square color and circle color, just pick two colors and go with it.
I guess the reason for that is making the instructions understandable even if printing in b/w.
I think that's correct. If I were to do it for my kids I'd probably whip through and colour in the squares and circles beforehand to make it simpler for them
Also it works with colorblind people. This way they can choose the color combination that works for them.
I think it's just so you can choose two colors that you have and fill in the instructions.