Basic logic probe design help

I have to construct the logic probe shown on the computer. Some of the connections are not shown though. After, i need to test it and make sure it works. D1, D2, D3, D4 are diodes. D5 and D6 are LEDs. 1 LED needs to be red, the other green (to show high/low). Im lost onto how to connect the switch/switches the right way. I believe thats the only thing that is missing? Here is the picture of the probe/schematic which is not showing all the connections.

https://imageshack.us/photo/my-images/210/logicprobe.jpg/

Any help would be greatly appreciated. Thanks.

Quite simply. Where it says red, you put your power lead positive. Where it says black you put your negative lead. The only switching point I can see is between the 3.9K resistor and the 'already placed' black lead. Short it to the black lead to check for TTL. Leave it disconnected otherwise.

Here is a simpler circuit: