For best results, don't use the NS-2 like a normal pedal (in one side, out the other). You want to plug into the input, then run the pedal's send into your other pedals, then into your amp, then plug your effects loop send into the pedal's return, and then the pedal's output into your effects loop return.
This way your initial clean guitar signal controls the gate, but the actual gating takes place after all your gain stages. If you just plug it in in front of the amp, even when the pedal cuts off the silence will turn into noise when it goes through your amp's overdrive. If you just put it in the effects loop, by the time the signal hits the pedal there will be too much noise for it to work properly.
Sorry if this is totally obvious!