Getting back into using oil paints again, this chap I did a lot of studies of many years ago, but not in oil. I buy lots those tester pots of decorating paints, and use them for a ground before oil painting. There are some lovely colours. For this portrait I did a ground of blue/green colour, bits of which peep through the final painting. An old trick we were taught at art college was you pick the worst colour you can find in your paintbox – something really garish – cover the entire canvas with it and then start painting.

You are so keen to cover up the terrible colour it makes you work quicker, but also has the pleasing effect that when the painting is completed you get tiny flecks of the ground colour peeping through, and it gives your painting a kind of ‘buzz’.