When I start a major project like that the first thing I do is get a good sized box (about two by tree feet). Then I check to see I have all of the tools for the job. Wrenches, tire irons, allen wrenches spoke tools (don't forget zip ties for things like head sets) . Next do you have a place you can work on it and leave it there over night? a project that big will take more than a day.
I like to work with my bike hanging off the ceiling with a block and tackle. Lately I have been using a repair stand I got from Performance Cycle. Park makes a good home one also but even there "cheep" on is more than you will pay for a overhaul.
Next step is to take it down to the frame. What you are doing is what I used to call is a complete overhaul. You will need to have some other boxes and some mid size zip lock bags. Make sure they are pretty strong. So when you take the Derailleurs off you can put it in its own bag. same thing with all of the parts.
Sheldon's web-sight can give you the particulars.
Harris Cyclery-West Newton, Massachusetts Bicycle Shop
Next, take a old tooth brush and some cleaner and spend a hour or two cleaning up all of the parts you just took off and bagged. After they have been cleaned they should be lubricated with ether grease or teflon based spray(NOT WD40) replace the parts that are worn or broken and reassemble.
or you can take it to a local bike shop or buy a new one and have the local shop assemble it and tune it up in about thirty days.