My boyfriend rang to wake me at six a.m. this morning. I've been having a hard time getting up early to go to the gym. I know it's essential – even if I didn't want to regain the slim, muscled body I had a few years ago, hard exercise is the only alternative to a dulling cocktail of mood stabilisers and anti-depressants – but in the middle of a southern autumn, when sunrise is still half an hour a way and the air cold, I can find plenty of excuses to stay in a warm bed.Sometimes, like the French novelist Colette (pictured), I work in bed. Propped up by large, soft pillows, my open laptop and cell phone beside me, I draw and paint on paper clipped to a square of thin plywood. Pollock-like streaks of ink or watercolours accumulate on the bed covers around me. I keep a pile of reference books, their pages marked with annotated Post-it notes, on the floor nearby and jars of water, spare brushes, pens and a notebook on the bedside table. As a comfortable combination of working and living space, a big bed – California king size – is hard to beat; if it's in a hotel room, even better because then I can call room service and not have to leave my bed to eat.Then again, once I'm out of bed, some atavistic urge overtakes me and I have to be in constant motion. A nomad by nature, I envy the street photographer or plein air painter who can wander far and wide in search of subject matter. It's too easy for me to settle, to hole up in one place. My art is never better for it.