This exercise wasn't as easy as I had thought. Finding the colours in the right balance proved to be a challenge. I spent many days looking for the perfect balance in situations around London rather than setting up a still life controlled by me.
I also learned that it is not always beneficial to underexpose to get a richer colour. For example, orange is richer when slightly underexposed, however this can make skin colour unacceptable.
I took loads of pictures until I got the selection below.