Do not ‘Think’ you have a book inside of you.
Go from ‘Think’ to ‘Do!’ by scribbling or typing some of it down -at least 1,000 words of it- without editing it as you go.
Do it today. Do not tear up what you’ve done, or allow yourself to listen to the voices telling you the premise is silly and that everyone’s going to hate your book. Wake up early and do the same thing tomorrow, and the next day. Then, keep going.
There is a book inside everyone.