If I had to describe myself to an alien I'd say I was bigger than the average human, enjoy a drink or two with a good meal and have a bigger head than most. I'd also say I'm really handsome - especially if they were a female alien. ↗
It comes down to something really simple: Can I visualize myself playing those scenes? If that happens, then I know that I will probably end up doing it. ↗
I keep one simple rule that I only move in one direction - I write the book straight through from beginning to end. By following time's arrow, I keep myself sane. ↗