Ok, let's do this...
When I was a kid, I used to experiment with electricity. I would hook things up on the floor of my room and learn how they worked. Maybe doing this would help you.
BEFORE doing any of the following, learn about electrical safety here...
http://www.wikihow.com/Master-Do-It-Yourself-Electrical-Safety
Ok, lets take this wiring diagram again...
http://www.electrical-online.com/Fall204.gif
On the left you have power coming in. A black and a white wire.
On the right you have a light also with a black and a white wire.
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If you were to use a wire with a plug on it and the wire had a black and a white wire, and you connected these to a light fixture which also had a black and white wire, then when you plugged the plug into an outlet, the light would go on. Unplug it, the light goes off.
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Switches....
There is an electrical tester called a continuity tester. Here is information about that...
http://en.wikipedia.org/wiki/Continuity_tester
You can take a regular light switch with two connections and connect a continuity tester to the two connections. Then turn the switch on/off and this will show the connection being made or broken.
Now take this switch and connect it between the black wire going from the plug to the light. So you have the plug white wire going to light white wire. And the plug black wire going to a switch connection. Then the light fixture black wire going to the other connection on the switch. Plug it in and turn the switch on/off and the light goes on off.
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Now take your continuity tester and see how a 3-way switch works. Hint: keep one lead on the "common" terminal.
Then do the same with a 4-way switch. Hint: look at the wiring diagram which came with the switch.
The continuity tester allows you to "see" what connections are being made/broken when each switch is in a certain position.
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Now remove the regular switch from the plug/light and wire in two 3-way switches. Here is the wiring diagram and some information...
http://home.howstuffworks.com/three-way2.htm
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Now connect a 4-way switch between the two 3-way switches. You will have plug, 3-way switch, 4-way switch, 3-way switch, then light fixture.
Here is a diagram and information for that...
http://www.wiringhelp.com/electrical/electrical-how-to/how-to-wire-a-4-way-switch.html
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Now if you can set this up and get it working on the floor, then all you need to do is label each connection or wire A, B, C, D, etc.
So here is that 4-way switch diagram again...
http://www.electrical-online.com/Fall204.gif
On the left you have black and white which is power. White connects through to white on the light fixture. Let's call white "A".
So "A" connects to white on the light fixture.
The power black wire - Let's say "B". This connects to the "common" terminal on the 1st 3-way switch.
Then there are two connections from the 3-way switch to the 4-way switch. Label these C and D. (Look at wiring diagram which comes with the 4-way switch for connections.)
Then there are two wires from the 4-way switch to the last 3-way switch. Let's call these E and F.
Then from that last 3-way switch there is a wire going from its common connection to the black wire on the light fixture. Let's call that wire G.