For Romex work I always reserve the top left ko for the hot and sometimes use the bottom left. I stick to this religiously and it sure cuts id time @ make up or when I have to return a year later to modify something.
When pushing a fish tape into a live panel I screw a rigid coupling onto the connector of the pipe entering the panel, then add a flex connector and a 3 foot length of alum. flex. You can have the fish tape emerge into the panel without danger of sticking it into the feeders or other embarrassing moves. For pipe entering from below, just tie the flex to the wires coming off the breakers to keep it stable.
When fishing, my all time favorite is my "Gold Fish" by ideal. I also carry a 25 ft. steel tape on a reel, a 15 ft. piece of bare fishtape (with loops on each end),and a few scraps of #6 solid ground wire and #8 TW. Something to use occassionally is a 12' length of steel strapping with the ends annealed, rounded over and punched. Found in a lumberyard dumpster, this is the cat's meow when fishing behind steel, al. & vinyl siding when you have to go up or down. Another tool I carry is a 12' brass safety loop chain with a 4 in. piece of # 6 soldered into the eye of one end to keep it from falling through the hole. this is the first fishing tool I learned to use.
Locating where to drill: insert a 3" gold colored decking screw into the finish floor 2" proud of the plate. When you are under the floor the bright screw is easy to locate and you know exactly where the center of the wall cavity is, relative to the screw. Don't insert the screw all the way down so that you mar the floor the least. A little dab of Water Putty seals the hole.
Locating: I did a house for a computer network admin. type and the drywallers hid a bunch of boxes. The client brought a tone generator, amplifier and detector from work and we found the hidden boxes in minutes. They are more better than my new $ 300 Amprobe Pasar.
