Locate your water main shutoff cover and use a crowbar to pry the cover off.
Shine your flashlight down the water main hole so you can get a visual idea of where the shutoff operating nut is.
Lower the curb key down into the hole and maneuver it until you feel the squared end slip tightly and firmly over the shutoff nut on the water main.
Twist the bolt all the way to the right to turn off the water flow to your residence. When you are finished and need to restore your water, insert the curb key and turn it fully to the left to open the water connection to your residence back up.