Call me Villa's picture shows it done correctly. and that's not a bad link either. Just be careful with the roof, it is the thing above your head, sounds like you've got a plan though and getting a good 3d model done of the house is the key. THE FIRST thing I did when I bought my house since I didn't get the blueprints (still bitter) is build a PRO-E 3D model of the house so I knew where everything was. I do that of every house I buy, well except Condos that'd be pointless. I then guessed at wiring locations etc, it has come in handy quite a bit since I've done so much work on the home. I also make notes on things as I go.
I took a thermal camera into my house and saw a cold wall that partitioned a 8ft ceiling to a vaulted ceiling. A few months later I went up in the attic for some other stuff saw a note about it and went over to where it was... The previous owner had run a new wire for a fan and didn't bother to put insulation up against the drywall where he had moved it away. Also left a blanket and a pillow... The only attic access is from the roof so it's crazy to think he would go up there with blown insulation and sleep but... why else would there be a pillow? 5sq ft of non insulated drywall... so I fixed that then did the rest... It's just a matter of doing one thing at a time as you can.