I never thought about it until you asked... so... thanks for asking.
For me there are two phases.
The first is everything that leads up to the release. The second is the release.
When everything comes together it's like this:
I pick my spot and, again if everything comes together, I really do see the flight of the arrow before release. I just know that I will hit where I want.
But the second part... well that's the tough one.
For me it feels a bit like losing my balance and at that curicial moment when all hope of recovery is lost I quit trying to keep my balance and, instead, jump. Like being a little kid at the pool's edge. You want to jump in, but you're a little afraid, so you lean forward in Olympic diving position, lean a little further, a little further and all of a sudden you are going to fall in. No stopping it, so you dive.
Does that make sense?