For Housewives
1. Take the desired/estimated time to project completion and multiply by 50, or 100 if it is winter.
2. When in doubt, assume the original electrician was dyslexic and had trouble differentiating between black and white wires. Assume that perhaps halfway through wiring a circuit, he changed his mind on which one should be line and which one should be neutral.
3. Assume that the people who did maintenance in subsequent years were not psychic and attempted to follow the standard convention that black is supposed to be line and white is supposed to be neutral. Also assume that if they followed this convention, they stood a 50/50 chance of being right - or wrong.
4. Remember, electricity is color blind and it doesn't care what color the wire insulation is.
5. Wash hands regularly and keep a large stock of hand lotion around, because unwrapping ancient electrical tape is really disgusting.
6. Occasional surprises may lurk in unforeseen locations. "Oh look, the metal detector picked up a junction box in the ceiling that was plastered over. And how does the power get from the kitchen ceiling to the kitchen outlet? Let's go lift some floorboards in the attic and go hunting for more junction boxes. Maybe they did an unconventional 'repair' after the roof fire in 1944."
7. When in doubt, disconnect every cable, switch, fixture, and outlet; then check the continuity of each wire, charting it's starting point and ending point. Make a diagram, because it will be impossible to remember it all.
8. On the diagram draw up a plan on how to reconnect everything in such a way that it actually follows standard wiring conventions and codes. I wish you the best of luck with that.
7. Last but not least, wear a shirt that does't have a loose neck, because in addition to the rule that the mounting screw from the ceiling light fixture will fall and roll to the least accessible place in the room, another rule applies to ladies. Invariably, that mounting screw with 60 years of accumulated grime on it will fall down your shirt and get stuck in your bra. Best of luck ladies.