Start colouring the koi fish. In order to make the colours shine particularly brightly, you should layer several colours on top of each other. Shade the red back of the koi fish slightly with cadmium yellow 107, then add a little bit of dark cadmium orange 115. Do not shade the entire area, leave out certain parts. Finally add an intensive layer of pale geranium lake 121. Shade the sides and the head of the koi fish partly with warm grey II 271, then with light ultramarine 140, cadmium yellow and dark cadmium orange. Colour the mouth with dark cadmium orange and pale geranium lake.

Shade the red parts of the second koi fish the same way as the first fish. The dark red part consists of warm grey II, pale geranium lake and magenta 133. For the area below the eye use warm grey II, cadmium yellow and dark cadmium orange.

Shade the red area in the middle with cadmium yellow, dark cadmium orange and pale geranium lake. Colour the mouth with magenta. Shade the sides with cadmium yellow, dark cadmium orange and a little bit of warm grey V. Work over the area with a wet paint brush.
Pick up a little bit of black pigment directly from the pencil and draw the eyes and the black areas. For accents and highlights you may also draw onto the wet areas directly with the pencil (see final result).