I'm gonna go against the grain. I don't. Unless I know I'm there a while , or at night so I'm not blinding the car behind with my foot on the brake continuously. Basically as often as I'd be putting on the handbrake in a manual car.
Don't know about the GS, but in the GT (F1 box) if it's in gear, and foot off the brake, it does not creep forward, therefore the clutch plates are not touching.... So no wear. Only when you touch the throttle, does it start to engage.
So, in your GS in 1st, foot off brake, does it creep forward? If the answer is yes, then putting it in Neutral will save some clutch wear.
However, obviously everytime you change gear, or put in N, your wearing other parts like your actuators and shift forks etc... So horses for courses.