How can I play an electric guitar through the n-Track effects systems without recording the sound?

From N-Track Wiki

The program can process the incoming in realtime when the "live input processing" mode is enabled. This mode is enabled when the "Live" button on the toolbar is pressed. When in live-input processing mode you will see the signal coming from your guitar in the vu-meter and you will be able to hear it from the output of the soundcard. If this is not happening, open the Windows volume control and make sure that the correct recording source is selected (mic or line input), that the signal level is correct and the same thing for the output of the soundcard. As for the cable connections, you may use the computer in the guitar amplifier effect loop or you can for example connect the line out of the amplifier to the line in of the soundcard and listen to the output connecting the soundcard's line out to a stereo amplifier. The latest versions of n-Track allow to playback and record with the live input processing on, so for example a guitar player can theoretically connect the guitar direcly to the computer, obtain the desired sound using plug-ins (good guitar distortion and other kind of plug-ins can be found on the Plugins page), then record tracks hearing the guitar sound through the computer. The tracks will be actually recorded clean, so that after the recording it will still be possible to change the guitar sound simply changing the plug-ins parameters. You may even record the guitar distorted, then decide that you prefer it clean, and obtain the desired sound without having to record the track again!