Start in the Middle (2010)

I'm no developer, but I took an introductory programming course in uni. I remember for our exam (code a specific game in python), I spent literally days getting nowhere, because I just couldn't figure out how to implement the beginning. One day, out of frustration more than anything, I made a function that was smack dab in the middle of the game with no scaffolding to make it work. That helped me realize its relationship to the next function near the middle, and so on. Before I knew it, the whole game had materialized as if by itself out of my fingertips.

That was the most flow-y state I've experienced in my life.

This is also pretty good advice for game design/development too. With the added benefit that if you make the first level/area/battle last, then you'll have enough experience with the setup to make a really strong first impression.

But yeah, I do this for both writing and programming, at least to some degree.