Question for an electrical dummy (me).

Replacing a single switch in my boy's bathroom. He leaves it on constantly so I am looking to replace it with a motion detection switch. Switch I am replacing is a simple 2 screw switch. The motion-detection switch has 4 wires.

The blue wire I know I won't use because that is for a 3-way switch which I am not doing. As an aside, can I simply cut this wire off? Will the exposed wire be hot? Do I need to tape this up?

There is a black, red and green wire on the new switch.

Question is how do I swap these switches out?

The old switch had 2 black wires hooked to it. I believe I hook the new switch to these 2 black wires via the black and red wire on the new switch?

Green is ground but what do I run the green switch wire to? The bundle of bare wires in the box?

Sounds like you got it. and yes, a jumper from the new switch to the bare wires in box.

Thanks guys. That's what I thought, but I prefer to err on the side of caution if I am not certain, particularly with something like electricity.