I think the way you're currently handling things is good enough, this is definitely one of the best explained guides that I've seen on here. I'd also just like to say thanks for posting all these updates today.
The only thing I can think of is perhaps hosting a copy of the site at each step (but all linked to the same database if possible) so that people can log into it there, and see if theirs matches the way it's meant to be at the step they're currently at. I think it'd aid the troubleshooting process for when things go wrong, and also show the progress of the project. Just a consideration. :)