That works, or, you could also splice the switch somewhere in the positive to the output jack. The first way is easier though...
Damn, look what buckethead started, lol.
i learnt this the hard way (and from people on this forum) that just using a switch to cut the hot lead will make a popping noise when you click it off, the way to stop the popping is to wire it to the ground, "shorting" the circuit out and stopping that nasty popping noise.