I first waxed my board following snowolf's video back in like 2008 (thanks).
What I've learned over the years is you're probably going to screw up at least a few wax jobs, especially when beginning (that's why it's good to have a used board to practice on). Until then, you're probably going to over heat, over wax, over scrape, etc, etc, until you develop your own system for going about the process.
Things get even more complicated when you start tuning your own edges (so it's good to dive in and start acclimating yourself to that early on as well)
the more your board gets hammered by the mtn (that first big core shot is a killer), the less you're going to care if it's "perfect", anyhow (it's never perfect) - you'll get over your waxing mistakes.