There’s only so much you can get out of preparation.
If you want to teach someone to swim there’s certainly no harm in explaining the basics to them and giving them an idea of what to expect, but when it comes down to it there’s no substitute for getting in the water.
In fact, explaining nothing and giving them a shove is often the best method. Certainly the quickest.
Will they panic and flail around making things worse? Most likely, yes. But they’ll figure it out. They won’t drown (even if it feels like they’re going to).
With writing—and pretty much everything else—preparation only gets you to the edge of the swimming pool. The rest you can only learn by diving in.