Have more than one idea on the go at any one time. If it’s a choice between writing a book and doing nothing I will always choose the latter. It’s only if I have an idea for two books that I choose one rather than the other. I ­always have to feel that I’m bunking off from something.

We spent some time in our family talking about what's the trade-off we want to make. We ended up talking a lot about design, but also about the values of our family. Did we care most about getting our wash done in an hour versus an hour and a half? Or did we care most about our clothes feeling really soft and lasting longer? Did we care about using a quarter of the water? We spent about two weeks talking about this every night at the dinner table.

What we've done all of these years is very simple, is use the little tool, which is ask three whys in a row. Because the first why you always have a good answer for. The second why, it starts getting difficult. By the third why, you don't really know why you're doing what you're doing.

And this is my only pair of pants. These three glasses, I don’t even think about it because I just think about having enough.

Every morning, Monday to Friday, I get up at 7am and make my wife breakfast in bed.

I would like to write a play which doesn’t disappoint me 20 years later.

Because I loved it when I was young.

Just circumstance. I was running a small theatre group and somebody didn’t deliver a play.

Never take advice from anyone with no investment in the outcome.

I love making jam. Plum is best.