I did it with coloured pencils. It looks fine on paper, but not so much in the computer. You can see the picture resting at the bottom of this post. I just gave up and did other things.
But then I realized it would be a shame to ignore such a good photo and I drew it again. This time, I used ink and black marker (COPIC 0.1 and a black COPIC marker). I think it looks much better, but feel free to compare both versions for yourself. The black and white picture took me around a week.
Far from perfect, but I am not drawing this again 😀