During my years as a carpenter in heavy construction, that is construction of industrial and commercial projects such as mine buildings and machine bases to hospitals and schools, I've experienced first hand the various trades involved in my industry. Most men and women are conscientious tradespeople adept in their particular trade. As a carpenter I worked closely with the various trades and picked up some of their skills and knowledge along the way. I noticed with electricians, in particular, how organized and orderly their work was. Wires were routed along cable ways and into panel boxes in a very neat and orderly fashion. When I had the opportunity to wire my own house I bought a book on the Electrical Code and purchased a permit for homeowners doing their own wiring from my local government department. I used the principles I learned from watching electrical tradesmen and applied it with the code requirements as I read the book. As a backup I hoped the electrical inspector would slap my hand if I made a mistake. I was reprimanded on only one fault, not putting in a large enough breaker and cable to a 60 gallon hot water tank. The book suggested the wiring and breaker for a 40 gallon which was smaller. No problem, I easily changed the breaker and upgraded the wire accordingly. Luckily I had an inspector watching my back.
During the construction of this website, I've answered questions on simple electrical wiring problems. I want to make it clear here that those not experienced in the basic principles of electrical wiring of lights, plugs and switches in their home should not attempt it without realizing the consequences that their errors may have. If a fire was caused by your negligence or oversight your house insurance may not cover the damage. If removing the panel cover to change a breaker, even though the main breaker is turned off, the panel is still hot. Handling electricity in the home may cause serious injury, death or a fire.
If you want to do wiring in your home, I strongly recommend purchasing a book on the subject that is up to date with the current electrical codes and taking out a permit, if allowed, from your local jurisdiction. The permit provides a backup in case of error, although don't depend on the inspector finding every error you have made. Some homeowners, to reduce the electricians time and ultimately the cost of labor, make an agreement that the homeowner does the work under the supervision of the electrical contractor. This is another form of backup. Of course, the contractor usually has to be a friend or have the confidence in the homeowner to agree with such a proposal. If you are not willing to learn the electrical codes or do not feel confident in performing this work, by all means hire a professional contractor to do the job for you.
The following articles show the ways of connecting 3 way switches, etc. but by no means advocates changing the wiring in you home without the full knowledge of the electrical codes for your area and the consequences of your causing an accident.
Work Safe!!