What is the best step before beginning work with acrylic colour?

Correct answer: Prepare the outline, colour plan, and materials

The governing concept is organised preparation before execution. Before applying acrylic colour, the artist should establish the outline, decide the colour plan, and arrange suitable paints, brushes, water, and working surfaces. This sequence reduces interruptions and prevents avoidable mistakes, so option D is correct. Mixing every colour at once wastes paint and causes muddiness; soaking paper is not generally required for acrylics; and a dirty brush contaminates new colours. Planning improves control and efficiency.