"When I first started signing books, I spoke to the publishers at Hachette and said my signature is not great. And they said, 'I'm sure it will be fine' …  And I said, 'Look, I'll do my signature and send you a photo.'

"I sent it through and there was just this silence at the other end of the phone. And I said, 'So, what do you think?' And she said, 'Well, Susannah, I guess it would be great if any part of your signature resembled any part of your name.'"