Photo: Nick Briggs/Courtesy of Carnival Films

1. Years ago, after I left Cambridge and went to drama school, my friends who were going on to lead sane lives in banking or the army thought I was crazy. I had to stop seeing them and instead surround myself with people who believed I was talented and that it was all going to happen for me.

2. There are days when I realize I'm writing rubbish. But my solution is not to not write. I plan a plot structure, and usually the writer's block passes.

3. One thing I don't believe in is constantly going back over what I've done. Editing my scripts seems to be fruitful only once I've reached the end—when I have the broad strokes, the big picture. If I'm constantly going over what I wrote last Tuesday, it's difficult to actually finish it.

4. When I've exhausted my general fizz, I'll write the title of the next scene: "Dining Room, Day." I think it's a mistake to stop working without a clue as to what comes next.

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