Don’t run on neutral when driving downhill
When you put your gears in neutral when driving downhill, you are taking away from yourself the ability to control the car completely. You still have the capacity to use your brakes without any problems, but you cannot increase the speed instantly. And sometimes you may need some immediate acceleration.
Another advantage of keeping it in gear is that it saves fuel, by using the inertia of the car wheels rotating to power all the systems of your vehicle. So you should never use neutral when going downwards. This way you will improve your safety and fuel economy.