I did my first without brew software, and I spent a long time writing things down to make sure I wouldn't forget things. I still forgot things. It's easier with a brew sheet printed out by something with a brain less squishy than mine.
I'd measure everything you can whenever you can and take notes.
Mash tun dead space, pre-boil gravity, pre-boil volume, OG, post-boil volume, any changes you make on the fly (oops I put in my flavor addition 2 minutes late! etc).
You should measure temperature loss in your mash tun also to get an idea about what is happening in there during your mash. You might want to wrap it in a blanket if you're using a cooler.
Also, consider how you're going to be moving things around. Logistics can really get overwhelming.
Jesus, I re-read that post and it makes it sound like a nightmare, but if you think things through it really isn't.
It sounds like it will be a lot of fun.