I'll put my replies in point form for readability's sake:
[*]Very nice guide! 🙂
[*]Ground yourself!!! You should always connect the PSU to the wall and turn the switch to off before building!! This grounds the case and diminishes the risk of ESD damage. I also touch the ESD-safe bag of each component onto a metallic part of the case to make sure there will be no static later. Definitely put a note in about this, you could also put a note in about using an ESD bracelet if you want to be even more sure about static.
[*]You should put in a step to fire up the motherboard with only the RAM, CPU, and video. If it POSTs ok, then continue onwards, otherwise recheck everything (in particular grounding and placement of the standoffs).
[*]Showing how to install a PSU would be nice, since some cases don't come with a PSU. Maybe add that when you get a chance?
[*]Make a point of mentioning to beware of sharp case edges. First time builders could be surprised at how easily mangled you can get trying to put together a computer 😉
[*]Snacks shouldn't be greasy/make sure to wash hands between building time and snacking. Greasy hands + small screws = pain in the ass.
[*]You're a hairy beast! 😛